This study was performed to investigate the effect of melatonin on bovine oocyte maturation and subsequent embryonic development in vitro. The endogenous melatonin concentration in bovine follicular fluid is approximately 10(-11) M. To examine the potential beneficial effects of melatonin on bovine oocyte maturation in vitro, germinal vesicle (GV) oocytes were incubated with different concentrations of melatonin (10(-11), 10(-9), 10(-7), 10(-5), 10(-3) M). Melatonin supplementation at suitable concentrations significantly promoted oocyte maturation. The development of embryos and the mean cell number/blastocyst produced after in vitro fertilization were remarkably improved. The most effective melatonin concentrations obtained from the studies ranged from 10(-9) to 10(-7) M. The expression of melatonin receptor MT1 and MT2 genes was identified in cumulus cells, granulosa cells, and oocytes using reverse transcription PCR, immunofluorescence, and Western blot. The mechanistic studies show that the beneficial effects of melatonin on bovine oocyte maturation are mediated via melatonin membrane receptors as the melatonin receptor agonist (IIK7) promotes this effect while the melatonin receptor antagonist (luzindole) blocks this action. Mechanistic explorations revealed that melatonin supplementation during bovine oocyte maturation significantly up-regulated the expressions of oocyte maturation-associated genes (GDF9, MARF1, and DNMT1a) and cumulus cells expansion-related gene (PTX3, HAS1/2) and that LHR1/2, EGFR are involved in signal transduction and epigenetic reprogramming. The results obtained from the studies provide new information regarding the mechanisms by which melatonin promotes bovine oocyte maturation in vitro and provide an important reference for in vitro embryo production of bovine and the human-assisted reproductive technology.
On the basis of Covid-19-induced pulmonary pathological and vascular changes, we hypothesize that the anti-vascular endothelial growth factor (VEGF) drug bevacizumab might be beneficial for treating Covid-19 patients. From Feb 15 to April 5, 2020, we conducted a single-arm trial (NCT04275414) and recruited 26 patients from 2-centers (China and Italy) with severe Covid-19, with respiratory rate ≥30 times/min, oxygen saturation ≤93% with ambient air, or partial arterial oxygen pressure to fraction of inspiration O2 ratio (PaO2/FiO2) >100 mmHg and ≤300 mmHg, and diffuse pneumonia confirmed by chest imaging. Followed up for 28 days. Among these, bevacizumab plus standard care markedly improves the PaO2/FiO2 ratios at days 1 and 7. By day 28, 24 (92%) patients show improvement in oxygen-support status, 17 (65%) patients are discharged, and none show worsen oxygen-support status nor die. Significant reduction of lesion areas/ratios are shown in chest computed tomography (CT) or X-ray within 7 days. Of 14 patients with fever, body temperature normalizes within 72 h in 13 (93%) patients. Relative to comparable controls, bevacizumab shows clinical efficacy by improving oxygenation and shortening oxygen-support duration. Our findings suggest bevacizumab plus standard care is highly beneficial for patients with severe Covid-19. Randomized controlled trial is warranted.
BackgroundExogenous melatonin could induce cashmere growth. However, induced growth of cashmere fleece by melatonin implants cannot be combined with the typical growth, resulting in earlier shedding followed by another cycle of cashmere growth. To address this issue, we examine the effects on the cashmere yield, fibre characteristics, and the growth and reproductive performance of cashmere goats of planned administration of melatonin.MethodsEighteen half-sib, female goats were assigned to two treatments (n = 9) including a control and a treatment where melatonin (2 mg/kg BW) was implanted at the end of April and end of June. Cashmere growth and shedding were observed for approximately 1 year following implantation. Fibre samples were collected monthly to determine cumulative cashmere length. Initiation and cessation dates for cashmere growth as well as the rate of cashmere growth were calculated. Cashmere yield, weight gain of dam, kidding date, litter size, and birth weight were also recorded.ResultsMelatonin implantation increased cashmere yield by 34.5 % (control 553.7 g vs. melatonin 745.0 g; P < 0.01), cashmere length by 21.3 % (control 95.2 mm vs. melatonin 115.4 mm; P < 0.01), and decreased fibre diameter by 4.4 % (control 14.6 μm vs. melatonin 14.0 μm; P < 0.03). In melatonin-treated goats, the average initiation date was earlier than in control goats (May 18, 2013 vs. July 2, 2013; P < 0.01) but there was a similar cessation date (March 22, 2014 vs. March 27, 2014). Consequently, the duration of cashmere growth was longer in melatonin-treated goats than in control goats (307 vs.270 days; P < 0.01). The final BW, average daily gain, kidding date, litter size, and birth weight were not influenced by melatonin implantation.ConclusionsThese data indicate that melatonin implantation (2 mg/kg BW) on two occasions (late April and June) increased cashmere yield by combining the induced growth of cashmere fleece with the typical growth and decreased the fibre diameter without changing dam growth rate or reproductive performance.
Mirabegron (Myrbetriq) is a β3-adrenoreceptor agonist approved for treating overactive bladder syndrome in human patients. This drug can activate brown adipose tissue (BAT) in adult humans and rodents through the β3-adrenoreceptor-mediated sympathetic activation. However, the effect of the mirabegron, approved by the US Food and Drug Administration, on atherosclerosis-related cardiovascular disease is unknown. Here, we show that the clinical dose of mirabegron-induced BAT activation and browning of white adipose tissue (WAT) exacerbate atherosclerotic plaque development. In apolipoprotein E −/− (ApoE −/− ) and low-density lipoprotein (LDL) receptor −/− (Ldlr −/− ) mice, oral administration of clinically relevant doses of mirabegron markedly accelerates atherosclerotic plaque growth and instability by a mechanism of increasing plasma levels of both LDL-cholesterol and very LDL-cholesterol remnants. Stimulation of atherosclerotic plaque development by mirabegron is dependent on thermogenesis-triggered lipolysis. Genetic deletion of the critical thermogenesis-dependent protein, uncoupling protein 1, completely abrogates the mirabegron-induced atherosclerosis. Together, our findings suggest that mirabegron may trigger cardiovascular and cerebrovascular diseases in patients who suffer from atherosclerosis. mirabegron | atherosclerosis | plaque instability | lipolysis | adipose tissue A therosclerosis, the thickening, hardening, and loss of elasticity of the arterial vessel wall, is the major cause of morbidity and mortality worldwide (1-4). Atherosclerotic lesions containing fatty plaques, cholesterol, and inflammatory cells are the primary causes of cardiovascular disease and stroke (5, 6). Atherosclerosis as a chronic and progressive disease usually starts with damage of the endothelial layer of an artery. Hypertension, hyperglycemia, hyperlipidemia especially hypercholesterolemia, smoking, obesity and diabetes, certain inflammatory disorders such as arthritis, infections, and drugs are the common risk factors of atherosclerotic plaque formation (7,8). Of interest, high incidences of myocardial infarction and stroke have been associated with colder ambient temperature and cold seasons (9, 10). Although the exact mechanism underlying low ambient temperature has not been elucidated, our recent findings show that cold-induced lipolysis in brown adipose tissue (BAT) and browning of white adipose tissue (WAT) may partly explain the high incidences of cardiovascular disease and stroke (11).The balance between energy deposition and dissipation is regulated by multiple factors, including the central nervous system, the endocrine system, food intake, physical exercise, pathological disease, and medications (12,13). Although WAT stores excessive energy in its lipid form, activated BAT specializes energy consumption by producing heat (14,15). Under certain conditions such as cold exposure, WAT, especially that located in the s.c. region, undergoes the brown-like transition, a process named browning WAT (16,17). Instead of stor...
SUMMARYTrichinella spiralis is a parasitic helminth that can infect almost all mammals, including humans. Trichinella spiralis infection elicits a typical type 2 immune responses, while suppresses type 1 immune responses, which is in favour of their parasitism. DNA vaccines have been shown to be capable of eliciting balanced CD4+ and CD8+ T cell responses as well as humoral immune responses in small-animal models, which will be advantage to induce protective immune response against helminth infection. In this study, serine protease (Ts-NBLsp) was encoded by a cDNA fragment of new-born T. spiralis larvae, and was inserted after CMV promoter to construct a DNA vaccine [pcDNA3·1(+)-Ts-NBLsp]. Ts-NBLsp expression was demonstrated by immunofluorescence. Sera samples were obtained from vaccinated mice, and they showed strong anti-Ts-NBLsp-specific IgG response. Mice immunized with the pcDNA3·1(+)-Ts-NBLsp DNA vaccine showed a 77·93% reduction in muscle larvae (ML) following challenge with T. spiralis ML. Our results demonstrate that the vaccination with pcDNA3·1(+)-Ts-NBLsp plasmid promoted the balance of type 1 and 2 immune responses and produced a significant protection against T. spiralis infection in mice.
The present study was set out to address the therapeutic efficacy of human adipose tissue stem cells derived extracellular vesicles (hADSC-Evs) in a mouse model of dry eye disease and to investigate the underlying mechanisms involved. hADSC-Evs eye drops were topically administered to mice that subjected to desiccating stress (DS). Clinical parameters of ocular surface damage were assessed with fluorescein staining, tear production and PAS staining. For in vitro studies, cell viability assay and TUNEL staining were performed in human corneal epithelial cells (HCECs) treated with hADSC-Evs under hyperosmotic media. In addition, immunofluorescent staining, Real-time PCR (qRT-PCR) and Western blots were used to evaluated NLRP3, ASC, caspase-1, and IL-1β expression levels. Compared with vehicle control mice, topical hADSC-Evs treated mice showed decreased corneal epithelial defects, increased tear production, decreased goblet cell loss, as well as reduced inflammatory cytokines production. In vitro, hADSC-Evs could protect HCECs against hyperosmotic stress-induced cell apoptosis. Mechanistically, hADSC-Evs treatment suppressed the DS induced rises in NLRP3 inflammasome formation, caspase-1 activation and IL-1β maturation. In conclusion, hADSC-Evs eye drops effectively suppress NLRP3 inflammatory response and alleviate ocular surface damage in dry eye disease. Dry eye disease (DED) is a highly prevalent ocular surface disorder in the world 1. It is estimated that more than 16 million adults are diagnosed DED in US, and the prevalence in Asia is even higher than in western countries 2,3. According to the reports of Dry Eye Workshop (DEWS II), DED is a multifactorial disease that characterized by loss of homeostasis of the tear film 4. The tear film instability causes symptoms of discomfort, itching, eye irritation, glare and blurry vision, leading to a reduction in quality of life. Although the pathogenesis of DED is not yet fully understood, mounting evidence showed that the "vicious cycle of inflammation", including tear film instability, tear hyperosmolarity, apoptosis of cornea/conjunctiva and elevated levels of pro-inflammatory cytokines, play a core driver in its initiation and progression 5,6. Accordingly, most of the treatments to date are focused on reducing inflammation and restoring normal tear film 7. Mesenchymal stem cells (MSCs) are self-renewing multipotent stromal cells that can be isolated from mesenchymal tissues such as bone marrow, adipose, umbilical cord, as well as other tissues 8. Due to their immunomodulatory and trophic characteristics, MSC-based therapeutic intervention has been explored in a variety of immune-mediated disorders, including dry eye disease 9-12. Although most of the results were promising, safety issues regarding MSC-based therapy are still a matter of concern. Extracellular vesicles, with nanosized diameter of 30-150 nm, are known as intercellular communication mediators by transferring various bioactive molecules (proteins, lipids and RNAs) 13. Recent studies revealed that MS...
Development of secondary hair follicles in early postnatal cashmere goats may be adversely affected by reactive oxygen species which cause oxidative stress. Because melatonin is a potent antioxidant and scavenger of free radicals, this study explored the effects of melatonin on secondary hair follicle development and subsequent cashmere production. It was found that the initiation of new secondary follicles in early postnatal Inner Mongolian cashmere goats of both melatonin‐treated and control goats occurred in the first 10 weeks of age. Melatonin promoted the initiation and maturation of secondary follicles and increased their population. Importantly, the beneficial effect of melatonin on secondary follicle population remained throughout life. As a result, melatonin increased cashmere production and improved its quality in terms of reduced fiber diameter. The mechanisms underlying the role of melatonin on secondary follicle development included the enhancement of activities of antioxidant enzymes, for example, superoxide dismutase and glutathione peroxidase (GSH‐Px), elevated total antioxidant capacity, and upregulated anti‐apoptotic Bcl‐2 expression and downregulated expression of the pro‐apoptotic proteins, Bax and caspase‐3. These results reveal that melatonin serves to promote secondary hair follicle development in early postnatal cashmere goats and expands our understanding of melatonin application in cashmere production. Melatonin treatment led to an increase in both the quantity and quality of cashmere fiber. This increased the textile value of the fibers and provided economic benefit.
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