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Retinol and Oligopeptide-Loaded Lipid Nanocarriers as Effective Raw Material in Anti-Acne and Anti-Aging Therapies.
Life (Basel)
Małgorzata Pawłowska, Marta Marzec, Waldemar Jankowiak +1 more
The use of lipid nanocarriers as components of cosmetic formulations may provide an opportunity to fully exploit the beneficial properties of pentapeptide-18 and retinol while reducing the undesirable effects that occur during retinoid therapy. This study aimed to evaluate the effectiveness of semi-solid formulations enriched with retinol and oligopeptide-loaded lipid nanocarriers. Solid lipid nanoparticles were produced using a high-shear homogenization method. The work included physicochemical characterization of the cosmetic products, and evaluation of their stability as well as their efficacy. The resulting semi-solid preparations were determined to be stable regardless of their storage temperature. No effect of the presence of lipid nanoparticles on the shelf-life stability of the cosmetic products was observed. A temperature of 25 °C was considered the recommended storage temperature for the tested semi-solid formulations. Beneficial effects of the cosmetic products were proven (in vivo study on volunteers), i.e., a significant reduction in the level of sebum secretion (anti-acne therapy) and a decrease in the number of facial wrinkles (anti-aging therapy). In addition, the protective properties of the lipid nanoparticles themselves against the skin were confirmed, reducing the irritating effect of retinol that is usually the case with classic retinoid therapies.
Sevoflurane Activates PI3K/AKT Signaling Pathway by Upregulating GDF11 Expression to Attenuate Ischemia/Reperfusion Injury in Cardiomyocytes.
Discov Med
Rong-Sheng Zhou, Xiao-Hong Xue, Yang Bi +4 more
Myocardial ischemia/reperfusion (I/R) injury stands as a primary contributor to ischemic heart disease. Sevoflurane (SEVO), a commonly used inhalation anesthetic, has been shown to exert a direct protective effect on ischemic heart injury. However, the specific mechanism by which it exerts the protective effect remains unclear. This study was designed to investigate the role of SEVO in myocardial I/R injury and its potential molecular mechanisms.
Antagonist of Growth Hormone-Releasing Hormone Receptor MIA-690 Suppresses the Growth of Androgen-Independent Prostate Cancers.
Int J Mol Sci
Laura Muñoz-Moreno, M Isabel Gómez-Calcerrada, M Isabel Arenas +4 more
The development of resistance remains the primary challenge in treating castration-resistant prostate cancer (CRPC). GHRH receptors (GHRH-R), which are coupled to G-proteins (GPCRs), can mediate EGFR transactivation, offering an alternative pathway for tumour survival. This study aimed to evaluate the effects of the GHRH-R antagonist MIA-690, in combination with the EGFR inhibitor Gefitinib, on cell viability, adhesion, gelatinolytic activity, and the cell cycle in advanced prostate cancer PC-3 cells. The findings demonstrate a synergistic effect between MIA-690 and Gefitinib, leading to the inhibition of cell viability, adhesion, and metalloprotease activity. Cell cycle analysis suggests that both compounds induce cell cycle arrest, both individually and in combination. Furthermore, similar effects of the GHRH-R antagonist MIA-690 combined with Gefitinib were observed in PC-3 tumours developed by subcutaneous injection in athymic nude mice 36 days post-inoculation. These results indicate that combined therapy with a GHRH-R antagonist and an EGFR inhibitor exerts a stronger antitumor effect compared to monotherapy by preventing transactivation between EGFR and GHRH-R in CRPC.
Proteins and Peptides from Food Sources with Effect on Satiety and Their Role as Anti-Obesity Agents: A Narrative Review.
Nutrients
Anaís Ignot-Gutiérrez, Gloricel Serena-Romero, Daniel Guajardo-Flores +3 more
Obesity, clinically defined as a body mass index (BMI) of 30 kg/m2 or higher, is a medical condition characterized by the excessive accumulation of body fat, which can lead to adverse health consequences. As a global public health issue with an escalating prevalence, controlling appetite and satiety is essential for regulating energy balance and managing body weight. Dietary proteins and peptides have gained interest in their potential to prevent and treat obesity by modulating satiety signals. This narrative review analyzes scientific evidence highlighting the role of dietary proteins and peptides in regulating satiety signals and investigates their therapeutic potential in preventing and treating obesity.
Ghrelin is essential for lowering blood pressure during torpor.
Front Endocrinol (Lausanne)
Kazuma Matsui, Takanori Ida, Kanae Oishi +2 more
Daily torpor is an active hypothermic phenomenon that is observed in some mammals and birds during fasting. A decrease in blood pressure has also been observed in torpor; however, there remains a lack of knowledge of the underlying mechanism. We have previously reported that ghrelin, an orexigenic hormone, has a hypothermic effect and is essential for the induction and maintenance of torpor. It is also known that the ghrelin secretion is enhanced during fasting and that ghrelin receptors are distributed in the cardiovascular system. Therefore, this study was conducted to test the hypothesis that ghrelin is actively involved in the regulation of blood pressure during torpor induction.
Pichia pastoris secreted peptides crossing the blood-brain barrier and DSIP fusion peptide efficacy in PCPA-induced insomnia mouse models.
Front Pharmacol
Xiaoxiao Mu, Lijun Qu, Liquan Yin +3 more
Pichia pastoris-secreted delta sleep inducing peptide and crossing the blood-brain barrier peptides (DSIP-CBBBP) fusion peptides holds significant promise for its potential sleep-enhancing and neurotransmitter balancing effects. This study investigates these properties using a p-chlorophenylalanine (PCPA) -induced insomnia model in mice, an approach akin to traditional methods evaluating sleep-promoting activities in fusion peptides.
The beneficial effects of modafinil administration on repeat mild traumatic brain injury (RmTBI) pathology in adolescent male rats are not dependent upon the orexinergic system.
Exp Neurol
Jennaya Christensen, Elaina Vlassopoulos, Christopher K Barlow +8 more
The sleep-wake cycle plays an influential role in the development and progression of repeat mild traumatic brain injury (RmTBI)-related pathology. Therefore, we first aimed to manipulate the sleep-wake cycle post-RmTBI using modafinil, a wake-promoting substance used for the treatment of narcolepsy. We hypothesized that modafinil would exacerbate RmTBI-induced deficits. Chronic behavioural analyses were completed along with a 27-plex serum cytokine array, metabolomic and proteomic analyses of cerebrospinal fluid (CSF), as well as immunohistochemical staining in structures important for sleep/wake cycles, to examine orexin, melanin-concentrating hormone, tyrosine hydroxylase, and choline acetyltransferase, in the lateral hypothalamus, locus coeruleus, and basal forebrain, respectively. Contrary to expectation, modafinil administration attenuated behavioural deficits, metabolomic changes, and neuropathological modifications. Therefore, the second aim was to determine if the beneficial effects of modafinil treatment were driven by the orexinergic system. The same experimental protocol was used; however, RmTBI rats received chronic orexin-A administration instead of modafinil. Orexin-A administration produced drastically different outcomes, exacerbating anxiety-related and motor deficits, while also significantly disrupting their metabolomic and neuropathological profiles. These results suggest that the beneficial effects of modafinil administration post-RmTBI, work independently of its wake-promoting properties, as activation of the orexinergic wake-promoting system with orexin-A was detrimental. Overall, these findings highlight the complexity of sleep-wake changes in the injured brain and showcase the potential of the arousal and sleep systems in its treatment.
Lacticaseibacillus paracasei NCU-04 relieves constipation and the depressive-like behaviors induced by loperamide in mice through the microbiome-gut-brain axis.
Curr Res Food Sci
Shengjie Li, Yi Li, Yujie Cai +5 more
Constipation is a prevalent gastrointestinal condition that significantly affects patients' physical and mental well-being, yet current treatments often lack safety and efficacy. Emerging evidence highlights the critical role of the microbiota-gut-brain axis (MBGA) in managing constipation, paving the way for probiotics as an adjuvant treatment to improve constipation symptoms. In this study, we isolated a gut probiotic strain, Lacticaseibacillus paracasei NCU-04, and investigated its improvement effects on loperamide-induced constipation in mice. We demonstrated that L. paracasei NCU-04 exhibited excellent probiotic properties, including robust growth, strong antibacterial and antioxidant capacities, and a lack of hemolytic activity in vitro. The administration of L. paracasei NCU-04 effectively improved the defecation-related indicators such as the fecal water content, time to the first black stool defecation, and intestine transit rate, suggesting enhanced gut immobility in constipated mice. Additionally, L. paracasei NCU-04 significantly reduced colon inflammation induced by loperamide. Further, L. paracasei NCU-04 increased levels of colonic motilin, 5-hydroxytryptamine (5-HT), and c-kit, while decreased that of aquaporin 3, vasoactive intestinal peptide, and peptide YY. Notably, L. paracasei NCU-04 effectively upregulated the expression of 5-HT and its receptor (i.e., 5-HT4R) in the brains of constipated mice. High-throughput sequencing revealed that L. paracasei NCU-04 restored the diversity and composition of the gut microbiota disturbed by loperamide, and significantly increased the relative abundance of Prevotella and Lactobacillus genera in the stool, while decreased that of Odoribacter, Rikenella, and Parabacteroides. Importantly, L. paracasei NCU-04 also effectively improved the depression-like behaviors associated with constipation, possibly through 5-HT mediated MGBA. These results suggest that L. paracasei NCU-04 may offer a promising approach for treating constipation and its related depressive symptoms, supporting its potential as a functional food or adjuvant therapy for human health.
Ghrelin is involved in regulating the progression of Echinococcus Granulosus-infected liver lesions through suppression of immunoinflammation and fibrosis.
PLoS Negl Trop Dis
Jiang Zhu, Hongqiong Zhao, Aili Aierken +6 more
Cystic Echinococcosis (CE) is a zoonotic disease causing fibrosis and necrosis of diseased livers caused by infection with Echinococcus granulosus (E.g). There is evidence that E.g is susceptible to immune escape and tolerance when host expression of immunoinflammation and fibrosis is suppressed, accelerating the progression of CE. Ghrelin has the effect of suppressing immunoinflammation and fibrosis, and whether it is involved in regulating the progression of E.g-infected liver lesions is not clear.
Single-cell and spatial transcriptomics reveal apelin/APJ pathway's role in microvessel formation and tumour progression in hepatocellular carcinoma.
J Cell Mol Med
Yongfu Zhu, Pengcheng Zhang, Xingxing Huo +4 more
The apelin receptor (APJ) is a key player in tumour angiogenesis, but its role in hepatocellular carcinoma (HCC) remains unclear. This study aims to elucidate the function of the apelin/APJ pathway in HCC using a multi-omics approach and identify potential therapeutic biomarkers. Differentially expressed genes related to the apelin/APJ axis were identified from bulk transcriptomics to reveal HCC-associated disparities. Single-cell and spatial transcriptomics were used to localize and analyse the function of these genes. Machine learning models were constructed to predict outcomes based on apelin/APJ expression, and experimental validation was conducted to explore the pathway's impact on HCC angiogenesis. Single cell analysis revealed an overexpression of APJ/Aplin in the endothelium. The stemness of endothelial cell (EC) with high apelin/APJ was enhanced, as well as the expression of TGFb, oxidative stresses and PI3K/AKT pathway genes. Spatial transcriptomics confirmed that EC populations with high APJ scores were enriched within the tumour. Machine learning models showed high prognostic accuracy. High APJ expression was linked to worse outcomes (p = 0.001), and AUC values were high (1 year, 3 year, 5 year) (0.95, 0.97, 0.98). Immune suppression and non-responsiveness of immune therapy were also seen in high-risk groups. The experimental validation showed that silencing apelin reduced angiogenesis (p  < 0.05), endothelial proliferation, decreased expression of ANG2, KLF2, VEGFA and lower ERK1/2 phosphorylation. Apelin may serve as a potential therapeutic target in HCC, given its role in promoting tumour angiogenesis and poor patient outcomes.
Growth differentiation factor 11 alleviates oxidative stress-induced senescence of endothelial progenitor cells via activating autophagy.
Stem Cell Res Ther
Ping Tao, Hai-Feng Zhang, Pei Zhou +3 more
Stem cell transplantation has been regarded as a promising therapeutic strategy for myocardial regeneration after myocardial infarction (MI). However, the survival and differentiation of the transplanted stem cells in the hostile ischaemic and inflammatory microenvironment are poor. Recent studies have focused on enhancing the survival and differentiation of the stem cells, while strategies to suppress the senescence of the transplanted stem cells is unknown. Therefore, we investigated the effect of growth differentiation factor 11 (GDF11) on attenuating oxidative stress-induced senescence in the engrafted endothelial progenitor cells (EPCs).
Ghrelin Modulates Voltage-Gated Ca2+ Channels through Voltage-Dependent and Voltage-Independent Pathways in Rat Gastric Vagal Afferent Neurons.
Mol Pharmacol
Hannah J Goudsward, Victor Ruiz-Velasco, Salvatore L Stella +2 more
The orexigenic gut peptide ghrelin is an endogenous ligand for the growth hormone secretagogue receptor type 1a (GHSR1a). Systemic ghrelin administration has previously been shown to increase gastric motility and emptying. While these effects are known to be mediated by the vagus nerve, the cellular mechanism underlying these effects remains unclear. Therefore, the purpose of the present study was to investigate the signaling mechanism by which GHSR1a inhibits voltage-gated Ca2+ channels in isolated rat gastric vagal afferent neurons using whole-cell patch-clamp electrophysiology. The ghrelin pharmacological profile indicated that Ca2+ currents were inhibited with a log (Ic50) = -2.10 ± 0.44 and a maximal inhibition of 42.8 ± 5.0%. Exposure to the GHSR1a receptor antagonist (D-Lys3)-GHRP-6 reduced ghrelin-mediated Ca2+ channel inhibition (29.4 ± 16.7% vs. 1.9 ± 2.5%, n = 6, P = 0.0064). Interestingly, we observed that activation of GHSR1a inhibited Ca2+ currents through both voltage-dependent and voltage-independent pathways. We also treated the gastric neurons with either pertussis toxin (PTX) or YM-254890 to examine whether the Ca2+ current inhibition was mediated by the Gα i/o or Gα q/11 family of subunits. Treatment with both PTX (Ca2+ current inhibition = 15.7 ± 10.6%, n = 8, P = 0.0327) and YM-254890 (15.2 ± 11.9%, n = 8, P = 0.0269) blocked ghrelin's effects on Ca2+ currents, as compared with control neurons (34.3 ± 18.9%, n = 8). These results indicate GHSR1a can couple to both Gα i/o and Gα q/11 in gastric vagal afferent neurons. Overall, our findings suggest GHSR1a-mediated inhibition of Ca2+ currents occurs through two distinct pathways, offering necessary insights into the cellular mechanisms underlying ghrelin's regulation of gastric vagal afferents. SIGNIFICANCE STATEMENT: This study demonstrated that in gastric vagal afferent neurons, activation of GHSR1a by ghrelin inhibits voltage-gated Ca2+ channels through both voltage-dependent and voltage-independent signaling pathways. These results provide necessary insights into the cellular mechanism underlying ghrelin regulation of gastric vagal afferent activity, which may benefit future studies investigating ghrelin mimetics to treat gastric motility disorders.
Changes of Transcriptomic Activity in Rat Brain Cells under the Influence of Synthetic Adrenocorticotropic Hormone-Like Peptides.
Biochemistry (Mosc)
Ivan B Filippenkov, Nataliya Y Glazova, Elena A Sebentsova +6 more
Synthetic peptides have a wide range of clinical effects. Of particular interest are peptides based on adrenocorticotropic hormone (ACTH) both as already used and as potential drugs for preventing consequences of cerebral ischemia. However, it is necessary to study influence of the peptide on the brain cells under normal physiological conditions, including understanding the risks of their use. Here, we used high-throughput RNA sequencing (RNA-Seq) to identify differentially expressed genes (DEGs) in the brain frontal cortex of rat receiving intraperitoneal administration of ACTH-like peptides ACTH(4-7)PGP (Semax) and ACTH(6-9)PGP, or saline. We identified 258 and 228 DEGs, respectively, with the fold change &gt; 1.5 and Padj &lt; 0.05 at 22.5 h after the first administration of Semax and ACTH(6-9)PGP. Metabolic pathways, characterizing both common and specific effects of the peptides on the transcriptome were identified. Both peptides predominantly caused decrease in expression of the genes associated with the immune system. At the same time, when comparing the effects of ACTH(6-9)PGP relative to Semax, DEGs were identified that characterized the main differences in the effects of the peptides. These genes were mostly downregulated and associated with neurosignaling systems and regulation of ion channels, thus characterizing differences in the effects of the peptides. Our data show how differences in the structure of ACTH derivatives are associated with the changes in the brain cell transcriptome following exposure to these related peptides. Furthermore, our results demonstrate that when studying influence of regulatory peptides on transcriptome under pathological conditions, it is necessary to take into account their actions under normal physiological conditions.
Role of spexin and DARS2 as potential biomarkers in basal cell carcinoma and cutaneous malignant melanoma diagnosis, and as therapeutic targets.
Arch Dermatol Res
Mehmet Mustafa Erdoğan, Songül Yerlikaya Kavak
Basal cell carcinoma (BCC) is a slowly progressive, locally aggressive and rarely metastasizing cancer, and although its mortality is low, its morbidity and cost of disease are high. While BCC is more common, cutaneous malignant melanoma (CMM) is significant due to its higher mortality rate. These patients can be treated, but recurrence, metastasis and mortality may occur in such patients. Various environmental, phenotypic and genotypic factors, especially ultraviolet (UV) radiations, play a role in the etiology of BCC and CMM. Histopathological examination continues to be the "gold standard" in their diagnosis. Spexin (SPX) and DARS2 are newly discovered proteins linked to many diseases, including cancer. These proteins may have an effect on the development and expression of skin cancers such as BCC and CMM. In this study, we evaluated the potential of SPX and DARS2 expressions as immunohistochemical biomarkers in the differential diagnosis of BCC and CMM. This study was conducted retrospectively using samples taken from the pathology laboratory. A total of 180 patient samples were used. The control group consisted of healthy skin tissues of the patients, and the other groups consisted of BCC and CMM tissues of the same patients. Tissue samples of all three groups were evaluated immunohistochemically with SPX and DARS2. The immunoreactivity of SPX was found to be higher in BCC and CMM tissue samples than in healthy skin tissues in the control group. DARS2 immunoreactivity was found to be higher in CMM tissues compared to the other two groups, and statistically significant in BCC tissues when compared with healthy control group tissues. SPX can be used as an immunohistochemical biomarker in the diagnosis of BCC and CMM. Since DARS2 expression is statistically more significant in CMM tissues than in BCC tissues, it can be used in differential diagnosis.
MOTS-c is an effective target for treating cancer-induced bone pain through the induction of AMPK-mediated mitochondrial biogenesis.
Acta Biochim Biophys Sin (Shanghai)
Long Yang, Miaomiao Li, Yucheng Liu +5 more
Bone cancer pain (BCP), due to cancer bone metastasis and bone destruction, is a common symptom of tumors, including breast, prostate, and lung tumors. Patients often experience severe pain without effective treatment. Here, using a mouse model of bone cancer, we report that MOTS-c, a novel mitochondrial-derived peptide, confers remarkable protection against cancer pain and bone destruction. Briefly, we find that the plasma level of endogenous MOTS-c is significantly lower in the BCP group than in the sham group. Accordingly, intraperitoneal administration of MOTS-c robustly attenuates bone cancer-induced pain. These effects are blocked by compound C, an AMPK inhibitor. Furthermore, MOTS-c treatment significantly enhances AMPKα 1/2 phosphorylation. Interestingly, mechanical studies indicate that at the spinal cord level, MOTS-c relieves pain by restoring mitochondrial biogenesis, suppressing microglial activation, and decreasing the production of inflammatory factors, which directly contribute to neuronal modulation. However, in the periphery, MOTS-c protects against local bone destruction by modulating osteoclast and immune cell function in the tumor microenvironment, providing long-term relief from cancer pain. Additionally, we find that chronic administration of MOTS-c has little effect on liver, renal, lipid or cardiac function in mice. In conclusion, MOTS-c improves BCP through peripheral and central synergistic effects on nociceptors, immune cells, and osteoclasts, providing a pharmacological and biological rationale for the development of mitochondrial peptide-based therapeutic agents for cancer-induced pain.
Thymosin α1 reverses oncolytic adenovirus-induced M2 polarization of macrophages to improve antitumor immunity and therapeutic efficacy.
Cell Rep Med
Kua Liu, Lingkai Kong, Huawei Cui +9 more
Although oncolytic adenoviruses are widely studied for their direct oncolytic activity and immunomodulatory role in cancer immunotherapy, the immunosuppressive feedback loop induced by oncolytic adenoviruses remains to be studied. Here, we demonstrate that type V adenovirus (ADV) induces the polarization of tumor-associated macrophages (TAMs) to the M2 phenotype and increases the infiltration of regulatory T cells (Tregs) in the tumor microenvironment (TME). By selectively compensating for these deficiencies, thymosin alpha 1 (Tα1) reprograms "M2-like" TAMs toward an antitumoral phenotype, thereby reprogramming the TME into a state more beneficial for antitumor immunity. Moreover, ADVTα1 is constructed by harnessing the merits of all the components for the aforementioned combinatorial therapy. Both exogenously supplied and adenovirus-produced Tα1 orchestrate TAM reprogramming and enhance the antitumor efficacy of ADV via CD8+ T cells, showing promising prospects for clinical translation. Our findings provide inspiration for improving oncolytic adenovirus combination therapy and designing oncolytic engineered adenoviruses.
The Top 5 Can't-Miss Sport Supplements.
Nutrients
Jose Antonio, Flavia Pereira, Jason Curtis +2 more
Background/Objectives: Sports supplements have become popular among fitness enthusiasts for enhancing the adaptive response to exercise. This review analyzes five of the most effective ergogenic aids: creatine, beta-alanine, nitrates, caffeine, and protein. Methods: We conducted a narrative review of the literature with a focus on the sport supplements with the most robust evidence for efficacy and safety. Results: Creatine, one of the most studied ergogenic aids, increases phosphocreatine stores in skeletal muscles, improving ATP production during high-intensity exercises like sprinting and weightlifting. Studies show creatine supplementation enhances skeletal muscle mass, strength/power, and muscular endurance. The typical dosage is 3-5 g per day and is safe for long-term use. Beta-alanine, when combined with the amino acid histidine, elevates intramuscular carnosine, which acts as a buffer in skeletal muscles and delays fatigue during high-intensity exercise by neutralizing hydrogen ions. Individuals usually take 2-6 g daily in divided doses to minimize paresthesia. Research shows significant performance improvements in activities lasting 1-4 min. Nitrates, found in beetroot juice, enhance aerobic performance by increasing oxygen delivery to muscles, enhancing endurance, and reducing oxygen cost during exercise. The recommended dosage is approximately 500 milligrams taken 2-3 h before exercise. Caffeine, a central nervous system stimulant, reduces perceived pain while enhancing focus and alertness. Effective doses range from 3 to 6 milligrams per kilogram of body weight, typically consumed an hour before exercise. Protein supplementation supports muscle repair, growth, and recovery, especially after resistance training. The recommended intake for exercise-trained men and women varies depending on their specific goals. Concluions: In summary, creatine, beta-alanine, nitrates, caffeine, and protein are the best ergogenic aids, with strong evidence supporting their efficacy and safety.
Synovial fluid alpha-defensins in Lyme arthritis-a useful marker.
Folia Microbiol (Praha)
Pavel Melicherčík, Matěj Mazura, Martin Hodík +7 more
Lyme arthritis, one of the possible late manifestations of Lyme borreliosis, predominantly affects the supporting joints and in adults most often occurs in the form of monoarthritis of the knee. Early diagnosis is based on clinical findings and serology. PCR detection of Borrelia in synovial fluid has become an integral part of the laboratory testing algorithm. The clinical presentation and inflammatory markers in Lyme arthritis can resemble septic arthritis. Determining the levels of alpha-defensins (human neutrophil peptide (HNP 1-3)) in synovial fluid by liquid chromatography is a highly sensitive method revealing the presence of inflammatory process. Between 2020 and 2022, we examined eleven patients with Lyme arthritis of the knee. We measured levels of HNP 1-3 from synovial fluid by HPLC in patients, and we compared it with the corresponding C-reactive protein (CRP) levels in paired serum samples. In patients diagnosed with Lyme arthritis, HNP 1-3 levels in synovial fluid ranged from 2.5 to 261 mg/L, with a median of 46.5 mg/L. Average serum CRP was 43 mg/L. The results show that elevated HNP 1-3 can be consistent with not only septic arthritis or systemic disease, but also with Lyme arthritis, especially in patients with negative culture and 16S PCR from synovial fluid. Final diagnosis must be verified by examination for anti-Borrelia antibodies from serum and synovial fluid. The aim of this work is to introduce an HPLC method for the determination of alpha-defensins as one of the possible diagnostic markers.
The Effects of Collagen Peptides as a Dietary Supplement on Muscle Damage Recovery and Fatigue Responses: An Integrative Review.
Nutrients
Pedro Augusto Querido Inacio, Yasmin Salgado Mussel Gomes, Ana Julia Nunes de Aguiar +5 more
The oral administration of hydrolyzed collagen peptides is a scientifically validated intervention for enhancing skeletal muscle health and performance. This integrative review consolidates the evidence supporting the use of low molecular weight collagen peptides (2000-3500 daltons) for their superior bioavailability and absorption. Our objective was to review the effects of collagen peptide or hydrolyzed collagen supplementation on muscle damage, recovery, and construction related to physical exercise.
Journey through the spectacular landscape of melanocortin 1 receptor.
Pigment Cell Melanoma Res
P R Upadhyay, V B Swope, R J Starner +2 more
The physiological role of α-melanocyte stimulating hormone in regulating integumental pigmentation of many vertebrate species has been recognized since the 1960's. However, its physiological significance for human pigmentation remained enigmatic until the 1990's. α-Melanocyte stimulating hormone and related melanocortins are synthesized locally in the skin, primarily by keratinocytes, in addition to the pituitary gland, and therefore act as paracrine factors for melanocytes. Human melanocytes express the melanocortin 1 receptor, which recognizes α-melanocyte stimulating hormone and the related adrenocorticotropic hormone as agonists. This review summarizes the current knowledge of the pleotropic effects of the activated melanocortin 1 receptor that maintain human melanocyte homeostasis by regulating melanogenesis and the response to environmental stressors, mainly solar radiation. Certain allelic variants of the melanocortin 1 receptor gene are associated with specific pigmentary phenotypes in various human populations. Variants associated with red hair phenotype compromise the function of the encoded receptor. Activation of the human melanocortin 1 receptor regulates eumelanin synthesis and enhances DNA damage response of melanocytes to solar radiation and oxidative stressors. We describe how synthetic selective melanocortin 1 receptor agonists can be efficacious as sunless tanning agents, for treatment of vitiligo and photosensitivity disorders, and for prevention of skin cancer, including melanoma.