Quercetin inhibits necroptosis in cardiomyocytes after ischemia-reperfusion via DNA-PKcs-SIRT5-orchestrated mitochondrial quality control.

We investigated the mechanism by which quercetin preserves mitochondrial quality control (MQC) in cardiomyocytes subjected to ischemia-reperfusion stress. An enzyme-linked immunosorbent assay was employed in the in vivo experiments to assess myocardial injury markers, measure the transcript levels of SIRT5/DNAPK-cs/MLKL during various time intervals of ischemia-reperfusion, and observe structural changes in cardiomyocytes using transmission electron microscopy. In in vitro investigations, adenovirus transfection was employed to establish a gene-modified model of DNA-PKcs, and primary cardiomyocytes were obtained from a mouse model with modified SIRT5 gene. Reverse transcription polymerase chain reaction, laser confocal microscopy, immunofluorescence localization, JC-1 fluorescence assay, Seahorse energy analysis, and various other assays were applied to corroborate the regulatory influence of quercetin on the MQC network in cardiomyocytes after ischemia-reperfusion. In vitro experiments demonstrated that ischemia-reperfusion injury caused changes in the structure of the myocardium. It was seen that quercetin had a beneficial effect on the myocardial tissue, providing protection. As the ischemia-reperfusion process continued, the levels of DNA-PKcs/SIRT5/MLKL transcripts were also found to change. In vitro investigations revealed that quercetin mitigated cardiomyocyte injury caused by mitochondrial oxidative stress through DNA-PKcs, and regulated mitophagy and mitochondrial kinetics to sustain optimal mitochondrial energy metabolism levels. Quercetin, through SIRT5 desuccinylation, modulated the stability of DNA-PKcs, and together they regulated the "mitophagy-unfolded protein response." This preserved the integrity of mitochondrial membrane and genome, mitochondrial dynamics, and mitochondrial energy metabolism. Quercetin may operate synergistically to oversee the regulation of mitophagy and the unfolded protein response through DNA-PKcs-SIRT5 interaction.

Discovery of a Novel Inhibitor Structure of Mycobacterium tuberculosis Isocitrate Lyase.

Tuberculosis remains a global threat to public health, and dormant Mycobacterium tuberculosis leads to long-term medication that is harmful to the human body. M. tuberculosis isocitrate lyase (MtICL), which is absent in host cells, is a key rate-limiting enzyme of the glyoxylic acid cycle and is essential for the survival of dormant M. tuberculosis. The aim of this study was to evaluate natural compounds as potential MtICL inhibitors through docking and experimental verification. Screening of the TCMSP database library was done using Discovery Studio 2019 for molecular docking and interaction analysis, with the putative inhibitors of MtICL, 3-BP, and IA as reference ligands. Daphnetin (MOL005118), with a docking score of 94.8 and -CDOCKER interaction energy of 56 kcal/mol, was selected and verified on MtICL in vitro and M. smegmatis; daphnetin gave an IC50 of 4.34 µg/mL for the MtICL enzyme and an MIC value of 128 µg/mL against M. smegmatis, showing enhanced potential in comparison with 3-BP and IA. The interactions and essential amino acid residues of the protein were analyzed. In summary, natural daphnetin may be a promising new skeleton for the design of inhibitors of MtICL to combat dormant M. tuberculosis.

Identification of therapeutic effect of glucagon-like peptide 1 in the treatment of STZ-induced diabetes mellitus in rats by restoring the balance of intestinal flora.

OBJECTIVE: The objective of this study was to identify the therapeutic effect and the underlying mechanism of glucagon-like peptide 1 (GLP-1) in the treatment of STZ-induced diabetes mellitus (DM). METHODS: Mice were treated with STZ to establish an animal model of DM, which was further treated with a GLP-1 receptor agonist. Subsequently, the status of glucose, insulin, nitric oxide, inflammatory and oxidative factors was evaluated and compared among Sham, STZ, and STZ + GLP-1 groups. In addition, the intestinal flora spectrum in each group was also evaluated. RESULTS: In this study, it was found that the administration of STZ increased the level of glucose and glycosylated hemoglobin but reduced the level of insulin. It was also found that the levels of inflammation and oxidative stress in STZ-induced DM were both enhanced, as evidenced by a decreased level of catalase, superoxide dismutase, glutathione peroxidase, as well as increased levels of malonyldialdehyde, interleukin-1ß (IL-1ß), and IL-6. Meanwhile, the expression of nitric oxide, a factor associated with both oxidative stress and inflammation, was also suppressed in STZ-induced DM. More importantly, the imbalance of intestinal flora was observed in STZ-induced DM, as shown by a decreased level of both total bacteria and that of some strains including Clostridium, Bacteroides, Lactobacilli, and Bifidobacteria. CONCLUSION: In summary, the findings of this study confirmed the antihyperglycemic effect of GLP-1 and demonstrated that the therapeutic effect of GLP-1 in the treatment of STZ-induced DM was mediated, at least partially, by its ability to restore the balance of intestinal flora.

A label-free fluorescence sensing strategy based on GlaI-assisted EXPAR for rapid and accurate quantification of human methyltranferase activity.

DNA methylation plays an important role in epigenetic modification. DNA methyltransferase (DNMT) is essential in the DNA methylation process, and its abnormal expression is closely related to cancer. In this study, we propose a novel biosensor platform (DS-GlaI-EXPAR) that combines hemi-methylated double-stranded DNA (dsDNA) as the substrate for DNMT1 with GlaI-assisted isothermal exponential amplification reaction (EXPAR) for rapid, simple, and sensitive detection of DNMT1 activity. The hemi-methylated dsDNA is fully methylated by DNMT1, and GlaI recognizes and cleaves the fully methylated sequence, generating terminal fragments that trigger EXPAR for efficient signal amplification. Whereas hemi-methylated dsDNA without DNMT1 will keep intact and cannot initiate EXPAR. DNMT1 activity can therefore be sensitively quantified by the real-time fluorescence signal of the DS-GlaI-EXPAR platform. The high-efficiency amplification of EXPAR and the recognition of GlaI enable the platform to overcome the inherent cumbersome and time-consuming shortcomings of traditional methods while meeting specificity and sensitivity. This DS-GlaI-EXPAR platform offers an impressively low limit of detection of 0.86 pg/µL and the entire detection process can be completed in a short time of 2.5 h in a single tube. Furthermore, DNMT1 activity detected by this platform in MCF-7 cells was significantly higher than that of HEK293 cells, and the inhibition of Apt. #9 was verified. This DNMT1 activity detection platform is very convenient and effective for the discovery of inhibitors and early cancer diagnosis.

The electrophysiological effects of Tongyang Huoxue granules on the ignition phase during hypoxia/reoxygenation injury in sinoatrial node cells.

Introduction: This study was undertaken to explore the potential therapeutic effects of Tongyang Huoxue Granules (TYHX) on sinoatrial node (SAN) dysfunction, a cardiac disorder characterized by impaired impulse generation or conduction. The research question addressed whether TYHX could positively influence SAN ion channel function, specifically targeting the sodium-calcium exchanger (I NCX) and L-type calcium channel (I CaL) of the SAN. Methods: Sinoatrial node cells (SANCs) were isolated and cultured from neonatal Japanese big-eared white rabbits within 24 h of birth. The study encompassed five groups: Control, H/R (hypoxia/reoxygenation), H/R+100 µg/mL TYHX, H/R+200 µg/mL TYHX, and H/R+400 µg/mL TYHX. The H/R model, simulating hypoxia/reoxygenation stress, was induced within 5 days of culture. Whole-cell patch clamp technique was employed to record currents following a 3-min perfusion and stabilization period with TYHX. Results: TYHX administration demonstrated improvements in the ignition phase of impaired SANCs. The half-maximal effective dose of TYHX, as determined by SANC beating frequency, was found to be 323.63 µg/mL. Inward current density of I NCX increased in response to TYHX (200 and 400 µg/mL), while TYHX enhanced I CaL current density in H/R SANCs, with 400 µg/mL exhibiting greater efficacy. Additionally, TYHX regulated the gating mechanisms of I CaL by right-shifting the steady-state inactivation curve and accelerating recovery from inactivation. Notably, TYHX increased the activation time constant under 200 and 400 µg/mL, prolonged the fast inactivation time constant τ1 with 400 µg/mL, and extended the slow inactivation time constant τ2 with 100 and 400 µg/mL. Discussion and conclusion: The findings suggest that TYHX may hold promise as a therapeutic intervention for sinus node dysfunction, offering potential avenues for drug development aimed at safeguarding SAN function.

Mechanisms involved in the regulation of mitochondrial quality control by PGAM5 in heart failure.

Heart failure (HF) refers to a group of clinical syndromes in which various heart diseases lead to the inability of cardiac output to meet the metabolic needs of the body's tissues. Cardiac metabolism requires enormous amounts of energy; thus, impaired myocardial energy metabolism is considered a key factor in the occurrence and development of HF. Mitochondria serve as the primary energy source for cardiomyocytes, and their regular functionality underpins healthy cardiac function. The mitochondrial quality control system is a crucial mechanism for regulating the functionality of cardiomyocytes, and any abnormality in this system can potentially impact the morphology and structure of mitochondria, as well as the energy metabolism of cardiomyocytes. Phosphoglycerate mutase 5 (PGAM5), a multifunctional protein, plays a key role in the regulation of mitochondrial quality control through multiple pathways. Therefore, abnormal PGAM5 function is closely related to mitochondrial damage. This article reviews the mechanism of PGAM5's involvement in the regulation of the mitochondrial quality control system in the occurrence and development of HF, thereby providing a theoretical basis for future in-depth research.

Roles and mechanisms of natural drugs on sinus node dysfunction.

Sinus node dysfunction is a common arrhythmia disorder with a high incidence and significant social and economic burden. Currently, there are no effective drugs for treating chronic sinus node dysfunction. The disease is associated with ion channel disturbances caused by aging, fibrosis, inflammation, oxidative stress, and autonomic dysfunction. Natural active substances and Chinese herbal medicines have been widely used and extensively studied in the medical community for the treatment of arrhythmias. Multiple studies have demonstrated that various active ingredients and Chinese herbal medicines, such as astragaloside IV, quercetin, and ginsenosides, exhibit antioxidant effects, reduce fibrosis, and maintain ion channel stability, providing promising drugs for treating sinus node dysfunction. This article summarizes the research progress on natural active ingredients and Chinese herbal formulas that regulate sick sinoatrial node function, providing valuable references for the treatment of sinus node dysfunction.

Triple-recognition strategy for one-pot detection of single nucleotide variants by aligner-mediated cleavage-triggered exponential amplification.

The detection of single nucleotide variants (SNVs) is important for the diagnosis and treatment of cancer. To date, researchers have devised several methods to detect SNVs, but most of them are complex and time-consuming. To improve SNVs detection specificity and sensitivity, we developed a triple-recognition strategy, which facilitates aligner-mediated cleavage-triggered exponential amplification (Trec-AMC-EXPAR) for the rapid, specific, and one-pot detection of SNV. Under optimized conditions, Trec-AMC-EXPAR detected two clinically significant SNVs, PIK3CAH1047R and EGFR L858R within 80 min, with a reliable detection of 0.1% SNV in the wide type, which is lower than that of allele-specific PCR (AS-PCR) for detecting SNV. Finally, by spiking into normal human serum samples, mutants mixed with the wild-type targets in different ratios were analyzed, resulting in the relative standard deviation (RSD) of recovery ratios <3%. The findings suggested the potential application of Trec-AMC-EXPAR in clinical disease diagnosis. In summary, the proposed Trec-AMC-EXPAR technique provides a novel fast and convenient method for one-pot detection of SNV with high sensitivity and specificity.

Reliability, validity, and sensitivity of short-form 36 health survey (SF-36) in patients with sick sinus syndrome.

Patients with sick sinus syndrome (SSS) experience a decrease in health-related quality of life (HRQoL), but there is currently no scale available to measure their unpleasant symptoms. The Short Form 36 Health Survey (SF-36) is a commonly used scale to assess HRQoL. In this study, we aimed to evaluate the reliability, validity, and sensitivity of SF-36 in patients with SSS. The sample included 199 eligible participants. We estimated the reliability through test-retest reliability, internal consistency, and split-half reliability. To examine the validity of the questionnaire, confirmatory factor analysis, convergent validity, and discriminant validity were conducted. Sensitivity was determined by the differences in age (cutoff 65 years) and New York Heart Association class. The intraclass correlational coefficients scores showed high test-retest reliability (intraclass correlational coefficients > 0.7). The overall Cronbach α was 0.87 (8 scales range: 0.85-0.87), showing good internal consistency reliability. The split-half reliability coefficient of the SF-36 is 0.814, indicating good reliability. Factor analysis showed that SF-36 subscales could be drawn into 6 components that explain 61% of the total variance. Results of model fit indicate comparative fit index = 0.9, incremental fit index = 0.92, Turker-Lewis index = 0.90, approximate root mean square error = 0.07, and normalized root mean square residual = 0.06. Convergent validity and discriminative validity showed adequate results. Comparison of different ages and New York Heart Association class groups showed statistical significance on most SF-36 subscales. We confirmed the SF-36 as a valid instrument for evaluating HRQoL patients with SSS. The reliability, validity, and sensitivity of SF-36 are acceptable for patients with SSS.

Zishenhuoxue decoction-induced myocardial protection against ischemic injury through TMBIM6-VDAC1-mediated regulation of calcium homeostasis and mitochondrial quality surveillance.

BACKGROUND: Zishenhuoxue decoction (ZSHX), a Chinese herbal medicine, exhibits myocardial and vascular endothelial protective properties. The intricate regulatory mechanisms underlying myocardial ischemic injury and its association with dysfunctional mitochondrial quality surveillance (MQS) remain elusive. HYPOTHESIS/PURPOSE: To study the protective effect of ZSHX on ischemic myocardial injury in mice using a TMBIM6 gene-modified animal model and mitochondrial quality control-related experiments. STUDY DESIGN: Using model animals and myocardial infarction surgery-induced ischemic myocardial injury TMBIM6 gene-modified mouse models, the pharmacological activity of ZSHX in inhibiting ischemic myocardial injury and mitochondrial homeostasis disorder in vivo was tested. METHODS: Our focal point entailed scrutinizing the impact of ZSHX on ischemic myocardial impairment through the prism of TMBIM6. This endeavor was undertaken utilizing mice characterized by heart-specific TMBIM6 knockout (TMBIM6CKO) and their counterparts, the TMBIM6 transgenic (TMBIM6TG) and VDAC1 transgenic (VDAC1TG) mice. RESULTS: ZSHX demonstrated dose-dependent effectiveness in mitigating ischemic myocardial injury and enhancing mitochondrial integrity. TMBIM6CKO hindered ZSHX's cardio-therapeutic and mitochondrial protective effects, while ZSHX's benefits persisted in TMBIM6TG mice. TMBIM6CKO also blocked ZSHX's regulation of mitochondrial function in HR-treated cardiomyocytes. Hypoxia disrupted the MQS in cardiomyocytes, including calcium overload, excessive fission, mitophagy issues, and disrupted biosynthesis. ZSHX counteracted these effects, thereby normalizing MQS and inhibiting calcium overload and cardiomyocyte necroptosis. Our results also showed that hypoxia-induced TMBIM6 blockade resulted in the over-activation of VDAC1, a major mitochondrial calcium uptake pathway, while ZSHX could increase the expression of TMBIM6 and inhibit VDAC1-mediated calcium overload and MQS abnormalities. CONCLUSIONS: Our findings suggest that ZSHX regulates mitochondrial calcium homeostasis and MQS abnormalities through a TMBIM6-VDAC1 interaction mechanism, which helps to treat ischemic myocardial injury and provides myocardial protection. This study also offers insights for the clinical translation and application of mitochondrial-targeted drugs in cardiomyocytess.

ß-tubulin contributes to Tongyang Huoxue decoction-induced protection against hypoxia/reoxygenation-induced injury of sinoatrial node cells through SIRT1-mediated regulation of mitochondrial quality surveillance.

BACKGROUND: TYHX-Tongyang Huoxue decoction has been used clinically for nearly 40 years. The ingredients of TYHX are Radix Astragali (Huangqi), Red Ginseng (Hongshen), Rehmannia Glutinosa (Dihuang), Common Yam Rhizome (Shanyao) and Cassia-bark-tree Bark (Rougui). Our previous experiments confirmed that TYHX can protect sinoatrial node cells. However, its mechanism of action is not completely understood yet. PURPOSE: The present study aimed to determine the protective effects of TYHX against Sinus node cell injury under hypoxic stress and elucidate the underlying mechanisms of protection. METHODS: Through RNA sequencing analysis and network pharmacology analysis, we found significant differences in mitochondrial-related genes before and after hypoxia-mimicking SNC, resolved the main regulatory mechanism of TYHX. Through the intervention of TYHX on SNC, a series of detection methods such as laser confocal, fluorescence co-localization, mitochondrial membrane potential and RT-PCR. The regulatory effect of TYHX on ß-tubulin in sinoatrial node cells was verified by in vitro experiments. The mechanism of action of TYHX and its active ingredient quercetin to maintain mitochondrial homeostasis and protect sinoatrial node cells through mitophagy, mitochondrial fusion/fission and mitochondrial biosynthesis was confirmed. RESULTS: Through RNA sequencing analysis, we found that there were significant differences in mitochondrial related genes before and after SNC was modeled by hypoxia. Through pharmacological experiments, we showed that TYHX could inhibit the migration of Drp1 to mitochondria, inhibit excessive mitochondrial fission, activate mitophagy and increase the mitochondrial membrane potential. These protective effects were mainly mediated by ß-tubulin. Furthermore, the active component quercetin in TYHX could inhibit excessive mitochondrial fission through SIRT1, maintain mitochondrial energy metabolism and protect SNCs. Our results showed that protection of mitochondrial function through the maintenance of ß-tubulin and activation of SIRT1 is the main mechanism by which TYHX alleviates hypoxic stress injury in SNCs. The regulatory effects of TYHX and quercetin on mitochondrial quality surveillance are also necessary. Our findings provide empirical evidence supporting the use of TYHX as a targeted treatment for sick sinus syndrome. CONCLUSION: Our data indicate that TYHX exerts protective effects against sinus node cell injury under hypoxic stress, which may be associated with the regulation of mitochondrial quality surveillance (MQS) and inhibition of mitochondrial homeostasis-mediated apoptosis.

The Effect of the Tongyang Huoxue Recipe (TYHX) on the I to/I Kur in Ischemia/Reperfusion Sinoatrial Node Cells.

Background: The transient outward potassium current (I to) and the ultrarapid delayed rectifier potassium current (I Kur) are major potassium currents involved in the repolarization process of sinoatrial node cells (SNCs). Methods and Results: The SNCs of neonatal rats were divided into control, ischemia/reperfusion (I/R), I/R+blank serum, and Tongyang Huoxue recipe (TYHX) serum groups. I to and I Kur were recorded using the whole cell patch-clamp technique, and the current-voltage (I-V), steady-state activation (SSA), steady-state inactivation (SSI), and recovery from inactivation (RFI) curves were plotted, respectively. Compared to the control group, both the peak current density and the current density at the voltage of I to and I Kur decreased obviously in SNCs after simulated I/R, the SSA curves moved right, and the SSI curves moved left. After TYHX was added to the extracellular solution of SNCs, both the peak current density and the current density at the voltage of I to and I Kur increased significantly, the SSA curves moved left, and the SSI curves moved right with a significant difference of V 1/2. The recovery from the I Kur RFI curves was slightly restored, and the I to curves did not change. Conclusions: TYHX increases the peak current density, accelerates the activation, and decreases the inactivation of the I to and I Kur. This may be the mechanism of TYHX in shortening the action potential duration of repolarization, which accelerates spontaneous pulsation.

One-pot synthesis of stable and functional hydrophilic CsPbBr3 perovskite quantum dots for "turn-on" fluorescence detection of Mycobacterium tuberculosis.

All-inorganic CsPbBr3 perovskite quantum dots (QDs) are widely studied owing to their excellent optoelectronic properties; however, they are usually hydrophobic and unstable in water and thus their biomedical applications are seriously limited. In this study, stable and hydrophilic CsPbBr3 QDs functionalized with carboxyl groups (CsPbBr3-COOH QDs) were prepared in one-pot with the aid of new ligands amino-poly(ethylene glycol)-carboxyl and perfluorooctyltriethoxylsilane. The aqueous solution of CsPbBr3-COOH QDs maintained the initial fluorescence intensity after 8 days of storage; the free carboxyl groups on the surface of CsPbBr3-COOH QDs were covalently conjugated with amino-terminal DNA to construct CsPbBr3 QDs-DNA probes for subsequent application. Then, a biosensing platform utilizing fluorescence resonance energy transfer between hydrophilic CsPbBr3 QDs-DNA and MoS2 nanosheets was developed for the sensitive and selective detection of the Mycobacterium tuberculosis DNA with a low limit of detection of 51.9 pM and the identification of drug-resistant clinical strains. This study advances the preparation of hydrophilic carboxyl-functionalized CsPbBr3 QDs with enhanced stability and extends their application in biomolecule detection.

A sensing strategy combining T7 promoter-contained DNA probe with CRISPR/Cas13a for detection of bacteria and human methyltransferase.

Abnormal DNA methylation is closely related to the occurrence and development of many diseases. The determination of human DNA methyltransferase activity and the screening of its inhibitors are extreme important for the diagnosis and the treatment of methylation-related diseases in clinic. Most of the current detection methods have the disadvantages of sophisticated design, high cost and low detection limit. By combining T7 promoter-contained DNA probe as the substrate for methyltransferase with CRISPR/Cas13a sensing strategy, a novel fluorescent sensing platform is designed to achieve simple, specific, sensitive detection of bacteria DNA methyltransferase (DNA-(N-6-adenine)-methyltransferase, Dam MTase) and also human methyltransferase (DNA (cytosine-5)-methyltransferase 1, Dnmt1). A hairpin DNA probe designed for Dam MTase and a double strand DNA probe for Dnmt1 are both methylated followed by the methylation-dependent site-specific cleavage, which result a T7 promoter-contained product and a T7 promoter-free one to respectively open and close the transcription and subsequent CRISPR/Cas13a target-initiated cleavage of fluorescence-labeled reporter RNA. In virtue of the specificity of methylation-dependent cleavage of probe, the efficient transcription amplification and CRISPR/Cas13a sequence-specific sensing, this strategy exhibited remarkable specificity and sensitivity, with the limit of detection of 3.10 × 10-5 U/mL for Dam MTase. Moreover, Dnmt1 activity in MCF-7 cells was detected and the inhibition of Apt. #9 was evaluated. This strategy for methyltransferase detection is convenient and efficient for inhibitor discovery and early cancer diagnosis.

Tongyang Huoxue Decoction (TYHX) Ameliorating Hypoxia/Reoxygenation-Induced Disequilibrium of Calcium Homeostasis and Redox Imbalance via Regulating Mitochondrial Quality Control in Sinoatrial Node Cells.

Sick sinus syndrome (SSS) is a disease with bradycardia or arrhythmia. The pathological mechanism of SSS is mainly due to the abnormal conduction function of the sinoatrial node (SAN) caused by interstitial lesions or fibrosis of the SAN or surrounding tissues, SAN pacing dysfunction, and SAN impulse conduction accompanied by SAN fibrosis. Tongyang Huoxue Decoction (TYHX) is widely used in SSS treatment and amelioration of SAN fibrosis. It has a variety of active ingredients to regulate the redox balance and mitochondrial quality control. This study mainly discusses the mechanism of TYHX in ameliorating calcium homeostasis disorder and redox imbalance of sinoatrial node cells (SANCs) and clarifies the protective mechanism of TYHX on the activity of SANCs. The activity of SANCs was determined by CCK-8 and the TUNEL method. The levels of apoptosis, ROS, and calcium release were analyzed by flow cytometry and immunofluorescence. The mRNA and protein levels of calcium channel regulatory molecules and mitochondrial quality control-related molecules were detected by real-time quantitative PCR and Western Blot. The level of calcium release was detected by laser confocal. It was found that after H/R treatment, the viability of SANCs decreased significantly, the levels of apoptosis and ROS increased, and the cells showed calcium overload, redox imbalance, and mitochondrial dysfunction. After treatment with TYHX, the cell survival level was improved, calcium overload and oxidative stress were inhibited, and mitochondrial energy metabolism and mitochondrial function were restored. However, after the SANCs were treated with siRNA (si-ß-tubulin), the regulation of TYHX on calcium homeostasis and redox balance was counteracted. These results suggest that ß-tubulin interacts with the regulation of mitochondrial function and calcium release. TYHX may regulate mitochondrial quality control, maintain calcium homeostasis and redox balance, and protect SANCs through ß-tubulin. The regulation mechanism of TYHX on mitochondrial quality control may also become a new target for SSS treatment.

Preventive Effects of Kaempferol on High-Fat Diet-Induced Obesity Complications in C57BL/6 Mice.

Kaempferol is a dietary flavanol that regulates cellular lipid and glucose metabolism. Its mechanism of action in preventing hepatic steatosis and obesity-related disorders has yet to be clarified. The purpose of this research was to examine kaempferol's antiobesity effects in high-fat diet- (HFD-) fed mice and to investigate its impact on their gut microbiota. Using a completely randomized design, 30 mice were equally assigned to a control group, receiving a low-fat diet, an HFD group, receiving a high-fat diet, and an HFD+kaempferol group, receiving a high-fat diet and kaempferol doses of 200 mg/kg in the diet. After eight weeks, the HFD mice displayed substantial body and liver weight gain and high blood glucose and serum cholesterol levels. However, treatment with kaempferol moderated body and liver weight gain and elevation of blood glucose and serum cholesterol and triglyceride levels. Examination of 16S ribosomal RNA showed that HFD mice exhibited decreased microbial diversity, but kaempferol treatment maintained it to nearly the same levels as those in the control group. In conclusion, kaempferol can protect against obesity and insulin resistance in mice on a high-fat diet, partly through regulating their gut microbiota and moderating the decrease in insulin resistance.

Changes of adipocytokine expression after diabetic rats received sitagliptin and the molecular mechanism.

OBJECTIVE: To study the effect of sitagliptin on adipocytokines expression in diabetic rats and its molecular mechanism. METHODS: Male SD rats were chosen and randomly divided into NC group, T2DM group, SP group and SP + LY group. NC group received conventional breeding, T2DM group, SP group and SP + LY group received intraperitoneal injection of streptozotocin after 12 weeks of high-fat diet to establish diabetes animal model, SP group received sitagliptin intervention and SP + LY group received sitagliptin combined with PI3K inhibitor LY294002 intervention. Six weeks after the intervention, serum was collected to determine the levels of biochemical indexes and adipocytokines, and visceral adipose tissue was collected to determine expression levels of adipocytokines. RESULTS: Serum TC, TG, LDL-C, FBG, FINS, Leptin and Chemerin levels as well as HOMA-IR of T2DM group were higher than those of NC group, and HDL-C, Adiponectin and Omentin-1 levels were significantly lower than those of NC group; serum TC, TG, LDL-C, FBG, FINS, Leptin and Chemerin levels as well as HOMA-IR of SP group were lower than those of T2DM group, and HDL-C, Adiponectin and Omentin-1 levels were significantly higher than those of T2DM group; Leptin and Chemerin levels in serum and visceral adipose tissue of SP + LY group were higher than those of SP group while Adiponectin and Omentin-1 levels were significantly lower than those of SP group. CONCLUSION: Sitagliptin can regulate the expression of adipocytokines in adipose tissue of diabetic rats through PI3K-AKT pathway.