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1.
Comp Biochem Physiol C Toxicol Pharmacol ; 287: 110038, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39260783

RESUMO

Time-restricted feeding (TRF) has the potential to modulate circadian rhythm and widely studied in humans and laboratory mice. However, less is known about the physiological responses to TRF in wild mammals. Here, we used Mongolian gerbils, Meriones unguiculatus, to explore the effect of 6-week TRF on gene expression related with circadian rhythm and inflammation. The TRF gerbils had higher cumulative food intake than the ad libitum (AL) group, but body mass, feeding frequency/time and metabolic rate did not differ between groups. In the hypothalamus, downregulation of rhythm-related genes Per3, Cry1 and Dbp was detected in the daytime-restricted feeding (DRF) group and Cry1 was downregulated in the nighttime-restricted feeding (NRF) group. In the liver, the expression of Per1/3, Rev-erbα/ß and Dbp was lower, and Bmal1 was higher in the DRF than in AL group, while NRF gerbils showed no changes. In the colon, the expression of Bmal1 and Cry1 was higher but Per3, Rev-erbα/ß and Dbp were lower in the DRF than in AL group. Further, the expression of inflammation-related genes such as NF-κB, IL-1ß, IL-18 and Nlrp3 was lower in the liver of DRF gerbils, and IL-1ß was lower both in the hypothalamus and liver of NRF gerbils. Moreover, the genes related with inflammation such as NF-κB, Nlrp3, IL-10/18/1ß and Tnf-α were positively or negatively correlated with multiple rhythm-related genes in the central and peripheral organs. In conclusion, TRF, particularly DRF, could modulate rhythm-related genes in the central and peripheral tissues and reduce hepatic expression of inflammation-related genes in gerbils.

2.
Front Mol Biosci ; 11: 1301099, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993839

RESUMO

Introduction: Hepatocellular carcinoma (HCC), which is closely associated with chronicinflammation, is the most common liver cancer and primarily involves dysregulated immune responses in the precancerous microenvironment. Currently, most studies have been limited to HCC incidence. However, the immunopathogenic mechanisms underlying precancerous lesions remain unknown. Methods: We obtained single-cell sequencing data (GSE136103) from two nonalcoholic fatty liver disease (NAFLD) cirrhosis samples and five healthy samples. Using pseudo-time analysis, we systematically identified five different T-cell differentiation states. Ten machine-learning algorithms were used in 81 combinations to integrate the frameworks and establish the best T-cell differentiation-related prognostic signature in a multi-cohort bulk transcriptome analysis. Results: LDHA was considered a core gene, and the results were validated using multiple external datasets. In addition, we validated LDHA expression using immunohistochemistry and flow cytometry. Conclusion: LDHA is a crucial marker gene in T cells for the progression of NAFLD cirrhosis to HCC.

3.
Acta Diabetol ; 61(9): 1097-1105, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38714558

RESUMO

AIM: Sodium-glucose cotransporter-2 inhibitors (SGLT2is) and glucagon-like peptide 1 receptor agonists (GLP-1RAs) are two new classes of antidiabetic agents. We aimed to evaluate the association between these two drug classes and risk of various vascular diseases, digestive diseases and fractures. METHODS: Large randomized trials of SGLT2is and GLP-1RAs were included. Outcomes of interest were the various serious adverse events related to vascular diseases, digestive diseases and fractures. We performed meta-analyses using synthesize risk ratio (RR) and 95% confidence interval (CI) as effect size. RESULTS: We included 27 large trials. SGLT2is had significant association with less hypertension (RR 0.70, 95% CI 0.54-0.91), hypertensive crisis (RR 0.63, 95% CI 0.47-0.84), varicose vein (RR 0.34, 95% CI 0.13-0.92), and vomiting (RR 0.55, 95% CI 0.31-0.97); but more spinal compression fracture (RR 1.73, 95% CI 1.02-2.92) and tibia fracture. GLP-1RAs had significant association with more deep vein thrombosis (RR 1.92, 95% CI 1.23-3.00), pancreatitis (RR 1.54, 95% CI 1.07-2.22), and cholecystitis acute (RR 1.51, 95% CI 1.08-2.09); but less rib fracture (RR 0.59, 95% CI 0.35-0.97). Sensitivity analyses suggested that our findings were robust. CONCLUSIONS: SGLT2is may have protective effects against specific vascular and digestive diseases, whereas they may increase the incidence of site-specific fractures (e.g., spinal compression fracture). GLP-1RAs may have protective effects against site-specific fractures (i.e., rib fracture), whereas they may increase the incidence of specific vascular and digestive diseases. These findings may help to make a choice between SGLT2is and GLP-1RAs in clinical practice.


Assuntos
Fraturas Ósseas , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon , Inibidores do Transportador 2 de Sódio-Glicose , Doenças Vasculares , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Doenças do Sistema Digestório/epidemiologia , Doenças do Sistema Digestório/etiologia , Doenças do Sistema Digestório/prevenção & controle , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia , Fraturas Ósseas/prevenção & controle , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Doenças Vasculares/epidemiologia , Doenças Vasculares/etiologia , Doenças Vasculares/prevenção & controle , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/efeitos adversos
4.
Artigo em Inglês | MEDLINE | ID: mdl-38723743

RESUMO

Ambient temperatures have great impacts on thermoregulation of small mammals. Brown adipose tissue (BAT), an obligative thermogenic tissue for small mammals, is localized not only in the interscapular depot (iBAT), but also in supraclavicular, infra/subscapular, cervical, paravertebral, and periaortic depots. The iBAT is known for its cold-induced thermogenesis, however, less has been paid attention to the function of BAT at other sites. Here, we investigated the function of BAT at different sites of the body during cold acclimation in a small rodent species. As expected, Brandt's voles (Lasiopodomys brandtii) consumed more food and reduced the body mass gain when they were exposed to cold. The voles increased resting metabolic rate and maintained a relatively lower body temperature in the cold (36.5 ± 0.27 °C) compared to those in the warm condition (37.1 ± 0.36 °C). During cold acclimation, the uncoupling protein 1 (UCP1) increased in aBAT (axillary), cBAT (anterior cervical), iBAT (interscapular), nBAT (supraclavicular), and sBAT (suprascapular). The levels of proliferating cell nuclear antigen (PCNA), a marker for cell proliferation, were higher in cBAT and iBAT in the cold than in the warm group. The pAMPK/AMPK and pCREB/CREB were increased in cBAT and iBAT during cold acclimation, respectively. These data indicate that these different sites of BAT play the cold-induced thermogenic function for small mammals.


Assuntos
Aclimatação , Tecido Adiposo Marrom , Arvicolinae , Temperatura Baixa , Termogênese , Proteína Desacopladora 1 , Animais , Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Marrom/metabolismo , Arvicolinae/fisiologia , Aclimatação/fisiologia , Proteína Desacopladora 1/metabolismo , Termogênese/fisiologia , Masculino , Regulação da Temperatura Corporal/fisiologia , Metabolismo Basal
5.
Ecol Evol ; 14(4): e11252, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38601856

RESUMO

The "pace-of-life" syndrome (POLS) framework can encompass multiple personality axes that drive important functional behaviors (e.g., foraging behavior) and that co-vary with multiple life history traits. Food hoarding is an adaptive behavior important for an animal's ability to adapt to seasonal fluctuations in food availability. However, the empirical evidence for the relationships between animal personality and hoarding behavior remains unclear, including its fitness consequences in the POLS framework. In this study, the Mongolian gerbil (Meriones unguiculatus), a social rodent, was used as a model system to investigate how boldness or shyness is associated with food hoarding strategies during the food hoarding season and their impact on over-winter survival and reproduction at both individual and group levels. The results of this study showed that, compared with shy gerbils, bold gerbils had a lower effort foraging strategy during the food hoarding season and exhibited lower over-winter survival rates. However, bold-shy personality differences had no effect on over-winter reproduction. These findings suggest that the personality is a crucial factor influencing the foraging strategy during the food hoarding season in Mongolian gerbils. Personality may be related to energy states or the reaction to environmental changes (e.g., predation risk and food availability) in bold or shy social animals. These results reflect animal life history trade-offs between current versus future reproduction and reproduction versus self-maintenance, thereby helping Mongolian gerbils in adapting to seasonal fluctuations in their habitat.

6.
Scand J Gastroenterol ; 59(4): 445-455, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38053282

RESUMO

BACKGROUND: Accompanied by the growing prevalence of nonalcoholic fatty liver disease (NAFLD), the coexistence of chronic hepatitis B (CHB) and NAFLD has increased. In the context of CHB, there is limited understanding of the factors that influence the development of NASH. METHODS: We enrolled CHB combined NAFLD patients who had liver biopsy and divided them to NASH vs. non-NASH groups. A whole transcriptome chip was used to examine the expression profiles of long noncoding RNAs (lncRNAs) and mRNA in biopsied liver tissues. The function analysis of HIGD1A were performed. We knocked down or overexpressed HIGD1A in HepG2.2.15 cells by transient transfection of siRNA-HIGD1A or pcDNA-HIGD1A. In vivo investigations were conducted using hepatitis B virus (HBV) transgenic mice. RESULTS: In 65 patients with CHB and NAFLD, 28 were patients with NASH, and 37 were those without NASH. After screening 582 differentially expressed mRNAs, GO analysis revealed differentially expressed mRNAs acting on nicotinamide adenine dinucleotide phosphate (NADPH), which influenced redox enzyme activity. KEGG analysis also shown that they were involved in the NAFLD signaling pathway. The function analysis revealed that HIGD1A was associated with the mitochondrion. Then, both in vivo and in vitro CHB model, HIGD1A was significantly higher in the NASH group than in the non-NASH group. HIGD1A knockdown impaired mitochondrial transmembrane potential and induced cell apoptosis in HepG2.2.15 cells added oleic acid and palmitate. On the contrary, hepatic HIGD1A overexpression ameliorated free fatty acids-induced apoptosis and oxidative stress. Furthermore, HIGD1A reduced reactive oxygen species (ROS) level by increasing glutathione (GSH) expression, but Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/Acetyl-CoA carboxylase (ACC) pathway was not involved. CONCLUSION: Both in vivo and in vitro CHB model, an upward trend of HIGD1A was observed in the NASH-related inflammatory response. HIGDIA played a protective role in cells against oxidative stress. Our data suggested that HIGD1A may be a positive regulator of NASH within the CHB context.


Assuntos
Hepatite B Crônica , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatite B Crônica/complicações , Fígado/patologia , Vírus da Hepatite B/genética , Espécies Reativas de Oxigênio/metabolismo
7.
Natl Sci Rev ; 10(10): nwad209, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37928774

RESUMO

Host phylogeny and environment have all been implicated in shaping the gut microbiota and host metabolic traits of mammals. However, few studies have evaluated phylogeny-associated microbial assembly and host metabolic plasticity concurrently, and their relationships on both short-term and evolutionary timescales. We report that the branching order of a gut microbial dendrogram was nearly congruent with phylogenetic relationships of seven rodent species, and this pattern of phylosymbiosis was intact after diverse laboratory manipulations. Laboratory rearing, diet or air temperature (Ta) acclimation induced alterations in gut microbial communities, but could not override host phylogeny in shaping microbial community assembly. A simulative heatwave reduced core microbiota diversity by 26% in these species, and led to an unmatched relationship between the microbiota and host metabolic phenotypes in desert species. Moreover, the similarity of metabolic traits across species at different Tas was not correlated with phylogenetic distance. These data demonstrated that the gut microbial assembly showed strong concordance with host phylogeny and may be shaped by environmental variables, whereas host metabolic traits did not seem to be linked with phylogeny.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37611884

RESUMO

In photoperiod-sensitive wild animals, the secretion of melatonin (MT) is modulated by external photoperiod, and MT affects inflammation and the ageing process. The beneficial effects of MT in delaying the progress of ageing have been reported in laboratory mice and rats. However, little is known about MT in wild mammals. In the current study, we investigated energy metabolism, microbial community structure and colon homeostasis in ageing Mongolian gerbils (Meriones unguiculatus) through exogenous supplementation of MT to test the hypothesis that MT has beneficial effects on gut homeostasis in ageing gerbils. Exogenous MT supplementation had no effect on energy metabolism in Mongolian gerbils but reduced the levels of circulating tumor necrosis factor-α (TNF-α), immune globulin G (IgG) and corticosterone (CORT). The increase in the level of inflammation in ageing animals was related to changes in the structure and diversity of the gut microbiota. At the genus level, the relative abundance of Prevotella, Treponema, Corynebacterium, and Sphingomonas was increased in ageing animals and decreased significantly by the treatment of MT. Christensenella and Lactobacillus were attenuated in ageing animals, and tended to be enhanced by MT treatment. Functions related to glycosphingolipid biosynthesis-ganglio series and lipopolysaccharide biosynthesis (metabolisms of cofactors, vitamins and glycan) were increased in ageing animals and decreased significantly by the treatment of MT. Our data suggest that a supplement of MT could improve colon homeostasis through changing the composition of gut microbiota and reducing inflammation in ageing gerbils.


Assuntos
Melatonina , Camundongos , Animais , Ratos , Gerbillinae , Melatonina/farmacologia , Inflamação/tratamento farmacológico , Metabolismo Energético , Colo , Envelhecimento
9.
BMC Nephrol ; 24(1): 215, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468857

RESUMO

AIM: To determine whether continuous venovenous hemodiafiltration (CVVHDF) plus standard medical therapy (SMT) vs. SMT alone prevents rhabdomyolysis (RM)-induced acute kidney injury (AKI) and analyze the related health economics. METHODS: This retrospective cohort study involved 9 RM patients without AKI, coronary heart disease, or chronic kidney disease treated with CVVHDF plus SMT (CVVHDF + SMT group). Nine matched RM patients without AKI treated with SMT only served as controls (SMT group). Baseline characteristics, biochemical indexes, renal survival data, and health economic data were compared between groups. In the CVVHDF + SMT group, biochemical data were compared at different time points. RESULTS: At 2 and 7 days after admission, serum biochemical indices (e.g., myoglobin, creatine kinase, creatinine, and blood urea nitrogen) did not differ between the groups. Total (P = 0.011) and daily hospitalization costs (P = 0.002) were higher in the CVVHDF + SMT group than in the SMT group. After 53 months of follow-up, no patient developed increased serum creatinine, except for 1 CVVHDF + SMT-group patient who died of acute myocardial infarction. In the CVVHDF + SMT group, myoglobin levels significantly differed before and after the first CVVHDF treatment (P = 0.008), and serum myoglobin, serum creatinine, and blood urea nitrogen decreased significantly at different time points after CVVHDF. CONCLUSIONS: Although CVVHDF facilitated myoglobin elimination, its addition to SMT did not improve biochemical indices like serum myoglobin, serum creatine kinase, creatinine, blood urea nitrogen, and lactate dehydrogenase or the long-term renal prognosis. Despite similar hospitalization durations, both total and daily hospitalization costs were higher in the CVVHDF + SMT group.


Assuntos
Injúria Renal Aguda , Terapia de Substituição Renal Contínua , Hemodiafiltração , Rabdomiólise , Humanos , Creatinina , Estudos Retrospectivos , Mioglobina , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Rabdomiólise/complicações , Creatina Quinase
10.
Int J Mol Sci ; 24(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37298074

RESUMO

Heat sensation and tolerance are crucial for determining species' survival and distribution range of small mammals. As a member of the transmembrane proteins, transient receptor potential vanniloid 1 (TRPV1) is involved in the sensation and thermoregulation of heat stimuli; however, the associations between animal's heat sensitivity and TRPV1 in wild rodents are less studied. Here, we found that Mongolian gerbils (Meriones unguiculatus), a rodent species living in Mongolia grassland, showed an attenuated sensitivity to heat compared with sympatrically distributed mid-day gerbils (M. meridianus) based on a temperature preference test. To explain this phenotypical difference, we measured the TRPV1 mRNA expression of two gerbil species in the hypothalamus, brown adipose tissue, and liver, and no statistical difference was detected between two species. However, according to the bioinformatics analysis of TRPV1 gene, we identified two single amino acid mutations on two TRPV1 orthologs in these two species. Further Swiss-model analyses of two TRPV1 protein sequences indicated the disparate conformations at amino acid mutation sites. Additionally, we confirmed the haplotype diversity of TRPV1 in both species by expressing TRPV1 genes ectopicly in Escherichia coli system. Taken together, our findings supplemented genetic cues to the association between the discrepancy of heat sensitivity and the functional differentiation of TRPV1 using two wild congener gerbils, promoting the comprehension of the evolutionary mechanisms of the TRPV1 gene for heat sensitivity in small mammals.


Assuntos
Regulação da Temperatura Corporal , Temperatura Alta , Animais , Gerbillinae/metabolismo , Regulação da Temperatura Corporal/genética , Aminoácidos/metabolismo , Variação Genética
11.
Obes Facts ; 16(5): 427-434, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37231905

RESUMO

INTRODUCTION: The prevalence of non-alcoholic fatty liver disease (NAFLD) in non-lean patients is significantly increased, and obesity significantly increases the risk of cirrhosis and HCC in NAFLD patients. However, whether there is a difference in clinical manifestations of NAFLD between overweight and obesity remains unclear. The objective of this study was to assess the clinical and histological features of NAFLD among a non-lean population. METHODS: Current study enrolled consecutive non-lean (body mass index [BMI] >23 kg/m2) patients with NAFLD and available liver biopsy results. Patients were stratified by BMI into two groups for the comparison of their clinical and histological variables, which included the overweight (BMI 23∼<28 kg/m2) and the obese (BMI ≥28 kg/m2). Risk factors for moderate to severe fibrosis (stage >1) were also analyzed through the logistic regression model. RESULTS: Among 184 non-lean patients with metabolic-associated fatty liver disease enrolled, 65 and 119 were overweight and obese, respectively. Patients in the obesity group had a significantly lower level of gamma-glutamyl transpeptidase, higher levels of platelet, glucose, prothrombin time, and more common of moderate to severe inflammatory activity when compared to those in the overweight group. However, a significant low frequency of moderate to severe fibrosis was found in the obesity group versus the overweight group (19.33% vs. 40.00%, p = 0.002). Binary logistics regression analysis of fibrosis found that aspartate transaminase (AST), BMI, alanine transaminase (ALT), and cholesterol (CHOL) were independent predictors for moderate to severe fibrosis in non-lean patients with NAFLD. Compared with the traditional fibrosis-4 (AUC = 0.77) and aminotransferase to platelet ratio index (AUC = 0.79) indexes, the combined index based on AST, BMI, ALT, and CHOL was more accurate in predicting moderate to severe fibrosis in non-lean patients with NAFLD (AUC = 0.87). CONCLUSIONS: Clinical and histological features differed between obesity and overweight patients with NAFLD. When compared to the traditional serum markers, the combination index including AST, BMI, ALT, and CHOL provided a better model to predict moderate to severe fibrosis in non-lean patients with NAFLD.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Sobrepeso/complicações , Carcinoma Hepatocelular/complicações , Neoplasias Hepáticas/complicações , Obesidade/complicações , Cirrose Hepática/complicações , Fibrose , Índice de Massa Corporal
12.
Mol Metab ; 73: 101724, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37061130

RESUMO

OBJECTIVE: Obesity in laboratory rodents is generally induced by feeding them a high fat diet (HFD). This model does not permit separation of the impact of the HFD from the resultant obesity on metabolic defects such as impaired glucose homeostasis. In Brandt's voles we have previously shown that exposure to long photoperiod (LD: 16L: 8D) induces obesity even when they are fed a low fat diet. We show here that these voles are largely resistant to HFD. This model therefore permits some separation of the effects of HFD and obesity on glucose homeostasis. The objective was therefore to use this model to assess if glucose homeostasis is more related to diet or obesity METHODS: Male voles, which were 35 days old and born in LD, were exposed to SD and a low fat diet for 70 days. We then randomly separated the animals into 4 groups for another 63 days: SL (short day and low fat diet: n = 19) group; SH (short day and high-fat diet, n = 20) group; LL (long day and low-fat diet, n = 20) group; LH (long day and high-fat diet, n = 18) group. Glucose tolerance tests (GTT) were performed after treatment for 56 days, and body compositions of the voles were quantified at the end by dissection. RESULTS: Consistent with our previous work LD voles were more obese than SD voles. Although total body weight was independent of dietary fat content, HFD did have an effect on fat storage. Photoperiod induced obesity had no effect on glucose homeostasis, and the fat content in both the liver and muscle. In contrast, HFD induced adiposity was linked with elevated fat deposition in muscle (but not in liver) and led to impaired glucose tolerance. CONCLUSIONS: The contrasting effects of diet and photoperiod were consistent with the predictions of the 'lipotoxicity hypothesis'. This may contribute to our understanding of why some human individuals are able to be obese yet remain metabolically healthy.


Assuntos
Dieta Hiperlipídica , Fotoperíodo , Animais , Masculino , Arvicolinae/metabolismo , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Homeostase , Obesidade
13.
NPJ Biofilms Microbiomes ; 8(1): 16, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379849

RESUMO

Regulating sodium and water balances is crucial for survival of small, desert mammals. Studies demonstrate that the gut microbiota and their metabolites are involved in host energy homeostasis, but little is known on the interactions among salt loading, gut microbiota, and osmoregulation. The aim of this study was to fill this gap. Mongolian gerbils (Meriones unguiculatus) were offered drinking water (Con) and either water containing moderate (4%, MS) or high NaCl (8%, HS) ad libitum. Intake of HS reduced α diversity of the microbial community and, at the genus level, reduced the relative abundances of Rikenella and Christensenella but increased Atopobium. To confirm the function of gut microbiota in host osmoregulation, we transplanted caecal microbiota in HS gerbils. To cope with salt loading, the gerbils concentrated urine, resulting in negative energy balance and systemic inflammation. The HS gerbils increased hypothalamic arginine vasopressin and intestinal and renal aquaporin 2 to support water retention, and reduced intestinal and renal epithelial sodium channel α to promote sodium excretion. However, HS gerbils with caecal microbiota transplant (CMT) from Con donors maintained energy balance and osmoregulation, and had a much reduced systemic inflammation. Further, CMT from Con donors to HS recipients reshaped the gut microbiota, particularly by reducing Parabacteroides distasonis and Prevotella copri, and increasing Lactobacillus reuteri abundances, with a resulting increase in bacterial metabolites such as butyrate. These findings highlight a vital role of the microbiota-gut-kidney axis in mediating salt-related osmoregulation, allowing small mammals to adapt to high salt loads in a desert habitat.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Rim , Mamíferos , Osmorregulação
14.
Front Physiol ; 13: 888324, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480035

RESUMO

The endotherms, particularly the small mammals living in the polar region and temperate zone, are faced with extreme challenges for maintaining stable core body temperatures in harsh cold winter. The non-hibernating small mammals increase metabolic rate including obligatory thermogenesis (basal/resting metabolic rate, BMR/RMR) and regulatory thermogenesis (mainly nonshivering thermogenesis, NST, in brown adipose tissue and skeletal muscle) to maintain thermal homeostasis in cold conditions. A substantial amount of evidence indicates that the symbiotic gut microbiota are sensitive to air temperature, and play an important function in cold-induced thermoregulation, via bacterial metabolites and byproducts such as short-chain fatty acids and secondary bile acids. Cold signal is sensed by specific thermosensitive transient receptor potential channels (thermo-TRPs), and then norepinephrine (NE) is released from sympathetic nervous system (SNS) and thyroid hormones also increase to induce NST. Meanwhile, these neurotransmitters and hormones can regulate the diversity and compositions of the gut microbiota. Therefore, cold-induced NST is controlled by both Thermo-TRPs-SNS-gut microbiota axis and thyroid-gut microbiota axis. Besides physiological thermoregulation, small mammals also rely on behavioral regulation, such as huddling and coprophagy, to maintain energy and thermal homeostasis, and the gut microbial community is involved in these processes. The present review summarized the recent progress in the gut microbiota and host physiological and behavioral thermoregulation in small mammals for better understanding the evolution and adaption of holobionts (host and symbiotic microorganism). The coevolution of host-microorganism symbionts promotes individual survival, population maintenance, and species coexistence in the ecosystems with complicated, variable environments.

15.
Int J Mol Sci ; 24(1)2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36613791

RESUMO

Skeletal muscle-based nonshivering thermogenesis (NST) plays an important role in the regulation and maintenance of body temperature in birds and large mammals, which do not contain brown adipose tissue (BAT). However, the relative contribution of muscle-based NST to thermoregulation is not clearly elucidated in wild small mammals, which have evolved an obligate thermogenic organ of BAT. In this study, we investigated whether muscle would become an important site of NST when BAT function is conditionally minimized in Brandt's voles (Lasiopodomys brandtii). We surgically removed interscapular BAT (iBAT, which constitutes 52%~56% of total BAT) and exposed the voles to prolonged cold (4 °C) for 28 days. The iBAT-ablated voles were able to maintain the same levels of NST and body temperature (~37.9 °C) during the entire period of cold acclimation as sham voles. The expression of uncoupling protein 1 (UCP1) and its transcriptional regulators at both protein and mRNA levels in the iBAT of cold-acclimated voles was higher than that in the warm group. However, no difference was observed in the protein or mRNA levels of these thermogenesis-related markers except for PGC-1α in other sites of BAT (including infrascapular region, neck, and axilla) between warm and cold groups either in sham or iBAT-ablated voles. The iBAT-ablated voles showed higher UCP1 expression in white adipose tissue (WAT) than sham voles during cold acclimation. The expression of sarcolipin (SLN) and sarcoplasmic endoplasmic reticulum Ca2+-dependent adenosine triphosphatase (SERCA) in skeletal muscles was higher in cold than in warm, but no alteration in phospholamban (PLB) and phosphorylated-PLB (P-PLB) was observed. Additionally, there was increased in iBAT-ablated voles compared to that in the sham group in cold. Moreover, these iBAT-ablated voles underwent extensive remodeling of mitochondria and genes of key components related with mitochondrial metabolism. These data collectively indicate that recruitment of skeletal muscle-based thermogenesis may compensate for BAT impairment and suggest a functional interaction between the two forms of thermogenic processes of iBAT and skeletal muscle in wild small mammals for coping cold stress.


Assuntos
Tecido Adiposo Marrom , Temperatura Baixa , Animais , Aclimatação/fisiologia , Tecido Adiposo Marrom/metabolismo , Arvicolinae/genética , Músculo Esquelético/metabolismo , RNA Mensageiro/metabolismo , Termogênese/genética , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
16.
Microb Biotechnol ; 15(3): 817-831, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33729663

RESUMO

Endothermic mammals have a high energy cost to maintain a stable and high body temperature (Tb , around 37°C). Thyroid hormones are a major regulator for energy metabolism and Tb . The gut microbiota is involved in modulating host energy metabolism. However, whether the interaction between the gut microbiota and thyroid hormones is involved in metabolic and thermal regulations is unclear. We hypothesized that thyroid hormones via an interaction with gut microbiota orchestrate host thermogenesis and Tb . l-thyroxine-induced hyperthyroid Mongolian gerbils (Meriones unguiculatus) increased resting metabolic rate (RMR) and Tb , whereas Methimazole-induced hypothyroid animals decreased RMR. Both hypothyroid and hyperthyroid animals differed significantly in faecal bacterial community. Hyperthyroidism increased the relative abundance of pathogenic bacteria, such as Helicobacter and Rikenella, and decreased abundance of beneficial bacteria Butyricimonas and Parabacteroides, accompanied by reduced total bile acids and short-chain fatty acids. Furthermore, the hyperthyroid gerbils transplanted with the microbiota from control donors increased type 2 deiodinase (DIO2) expression in the liver and showed a greater rate of decline of both serum T3 and T4 levels and, consequently, a more rapid recovery of normal RMR and Tb . These findings indicate that thyroid hormones regulate thermogenesis depending on gut microbiota and colonization with normal microbiota by caecal microbial transplantation attenuates hyperthyroid-induced thermogenesis. This work reveals the functional consequences of the gut microbiota-thyroid axis in controlling host metabolic physiology and Tb in endotherms.


Assuntos
Hipertireoidismo , Termogênese , Animais , Ceco/microbiologia , Gerbillinae/metabolismo , Hipertireoidismo/terapia , Termogênese/fisiologia , Hormônios Tireóideos/metabolismo
18.
Virus Res ; 298: 198405, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33775752

RESUMO

BACKGROUND/AIMS: To identify the inflammatory damage caused by chronic hepatitis B (CHB) in patients of chronic hepatitis B virus (HBV) infection complicated with non-alcoholic fatty liver disease (NAFLD), then guiding clinicians to carry out antiviral treatment. METHODS: According to the pathological features of liver biopsy, treatment-naïve obese patients of chronic HBV infection complicated with NAFLD who had elevated alanine transaminase (ALT) were divided into CHB group and NASH group. Transcriptome chips were used to analyze the expression profiles of long non-coding RNA (lncRNA) and mRNA in liver puncture tissues from the two groups. The chip data of CHB and NASH groups were analyzed for differential expression analysis, gene function analysis, signal pathway analysis, target gene prediction and competing endogenous RNAs (ceRNA) network analysis. RESULTS: By comparing CHB group with NASH group, a total of 44 differentially expressed lncRNAs and 567 differentially expressed mRNAs were screened. GO analysis predicted that the differentially expressed mRNAs may affect monooxygenase activity and oxidoreductase activity. KEGG analysis predicted that the differentially expressed mRNAs may be related to signaling pathways involved in oxidative phosphorylation, phagosomes, and NAFLD. Differential analysis of lncRNA shown that the expression of metastasis associated in lung adenocarcinoma transcript 1 (MALAT1) in CHB group was significantly upregulated. Subsequently, through target gene prediction and ceRNA network analysis, we found thioredoxin interacting protein (TXNIP), which was significantly upregulated in the CHB group and had a ceRNA relationship with MALAT1. It is predicted that there may be a ceRNA regulation relationship of MALAT1/hsa-miR- 20b-5p/TXNIP. CONCLUSION: The MALAT1/hsa-miR-20b-5p/TXNIP axis may mediate CHB-induced inflammatory damage in chronic HBV infection complicated with NAFLD, and the mechanism may be related to the activation of NLRP3 inflammatory bodies and downstream inflammatory responses.


Assuntos
Proteínas de Transporte , Hepatite B Crônica , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , RNA Longo não Codificante , Proteínas de Transporte/genética , Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Humanos , Inflamação , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , RNA Longo não Codificante/genética , RNA Mensageiro/genética
19.
World J Clin Cases ; 9(35): 10909-10918, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-35047601

RESUMO

BACKGROUND: Thumb polydactyly is one of the most common congenital hand deformities, and the Bilhaut-Cloquet procedure or a modified one is often used. However, controversy remains over the rare instances in which both thumbs are not of similar length or far apart in distance. AIM: To evaluate the clinical outcomes of pedicle complex tissue flap transfer in the treatment of duplicated thumbs with unequal size. METHODS: From January 2014 to December 2020, 15 patients underwent duplicated thumb reconstruction by pedicle complex tissue flap transfer at our hand surgery center. The technique was used when it was necessary to combine different tissues from both severed and preserved thumbs that were not of similar length or far apart in distance. Subjective parents' evaluations and functional outcomes (ALURRA and TATA criteria) were obtained. The alignment deviation, instability, range of motion (percent of opposite thumb) of the interphalangeal and metacarpophalangeal joints, and the aesthetic aspects, including circumference, length, nail size, and nail deformity, were used to assess the clinical outcomes. RESULTS: The average age of patients at the time of surgery was 13 mo, and the mean final follow-up occurred at 42 mo. An appropriate volume with a stable joint and good appearance was obtained in 14 reconstructed thumbs. An unstable interphalangeal joint occurred in one thumb. The flexion-extension arc at the metacarpophalangeal joint was good, while that at the interphalangeal joint was poor. Most of the parents were satisfied with the cosmetic and functional results of the reconstructed thumbs. The mean ALURRA score was 21.8 (range: 20-24), and the Tada score was 6.9 (range: 5-8). Compared with the non-operated side, the length of the operated thumb was approximately 95%, the girth was 89%, and the nail width was 82.9%. The mean ranges of motion were 62.1% of that of the unaffected thumb in the interphalangeal joint and 78.3% in the metacarpophalangeal joint. CONCLUSION: Harvesting a pedicle flap from a severed thumb is a safe and reliable procedure. Defects of the preserved thumb, such as the skin, nail, and bone, can be effectively restored using the complex tissue flap.

20.
mSystems ; 5(5)2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33082280

RESUMO

Ambient temperature (Ta ) is an important factor in shaping phenotypic plasticity. Plasticity is generally beneficial for animals in adapting to their environments. Gut microbiota are crucial in regulating host physiological and behavioral processes. However, whether the gut microbiota play a role in regulating host phenotypic plasticity under the conditions of repeated fluctuations in environmental factors has rarely been examined. We used intermittent Ta acclimations to test the hypothesis that the plasticity of gut microbiota confers on the host a metabolic adaptation to Ta fluctuations. Mongolian gerbils (Meriones unguiculatus) were acclimated to intermittent 5°C to 23°C, 37°C to 23°C or 23°C to 23°C conditions for 3 cycles (totally 3 months). Intermittent Ta acclimations induced variations in resting metabolic rate (RMR), serum thyroid hormones, and core body temperature (Tb ). We further identified that the ß-diversity of the microbial community varied with Ta and showed diverse responses during the 3 cycles. Some specific bacteria were more sensitive to Ta and were associated with host dynamic metabolic plasticity during Ta acclimations. In addition, depletion of gut microbiota in antibiotic-treated gerbils impaired metabolic plasticity, particularly at low Ta , whereas supplementation with propionate as an energy resource improved the inhibited thermogenic capacity and increased the survival rate in the cold. These findings demonstrate that both gut microbiota and their host were more adaptive after repeated acclimations, and dynamic gut microbiota and their metabolites may confer host plasticity in thermoregulation in response to Ta fluctuations. It also implies that low Ta is a crucial cue in driving symbiosis between mammals and their gut microbiota during evolution.IMPORTANCE Whether gut microbiota play a role in regulating host phenotypic plasticity in small mammals living in seasonal environments has rarely been examined. The present study, through an intermittent temperature acclimation model, indicates that both gut microbiota and their host were more adaptive after repeated acclimations. It also demonstrates that dynamic gut microbiota confer host plasticity in thermoregulation in response to intermittent temperature fluctuations. Furthermore, low temperature seems to be a crucial cue in driving the symbiosis between mammals and their gut microbiota during evolution.

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