Correlation of A2bAR and KLF4/KLF15 with Obesity-Dyslipidemia Induced Inflammation in Uygur Population

Therapeutic Targeting of Krüppel-Like Factor 4 and Its Pharmacological Potential in Parkinson's Disease: a Comprehensive Review

Krüppel-like factor 4 (KLF4), a zinc finger transcription factor, is found in different human tissues and shows diverse regulatory activities in a cell-dependent manner. In the brain, KLF4 controls various neurophysiological and neuropathological processes, and its contribution to various neurological diseases has been widely reported. Parkinson's disease (PD) is an age-related neurodegenerative disease that might have a connection with KLF4. In this review, we discussed the potential implication of KLF4 in fundamental molecular mechanisms of PD, including aberrant proteostasis, neuroinflammation, apoptosis, oxidative stress, and iron overload. The evidence collected herein sheds new light on KLF4-mediated pathways, which manipulation appears to be a promising therapeutic target for PD management. However, there is a gap in the knowledge on this topic, and extended research is required to understand the translational value of the KLF4-oriented therapeutical approach in PD.

PA and OA induce abnormal glucose metabolism by inhibiting KLF15 in adipocytes

Background

Obesity-induced elevated serum free fatty acids (FFAs) levels result in the occurrence of type 2 diabetes mellitus (T2DM). However, the molecular mechanism remains largely enigmatic. This study was to explore the effect and mechanism of KLF15 on FFAs-induced abnormal glucose metabolism.

Methods

Levels of TG, TC, HDL-C, LDL-C, and glucose were measured by different assay kits. qRT-PCR and Western Blot were used to detect the levels of GPR120, GPR40, phosphorylation of p38 MAPK, KLF15, and downstream factors.

Results

KLF15 was decreased in visceral adipose tissue of obesity subjects and high-fat diet (HFD) mice. In HFD mice, GPR120 antagonist significantly promoted KLF15 protein expression level and phosphorylation of p38 MAPK, meanwhile reduced the blood glucose levels. While, blocking GPR40 inhibited the KLF15 expression. In 3T3-L1 adipocytes, 1500 μM PA inhibited KLF15 through a GPR120/P-p38 MAPK signal pathway, and 750 μM OA inhibited KLF15 mainly through GPR120 while not dependent on P-p38 MAPK, ultimately resulting in abnormal glucose metabolism. Unfortunately, GPR40 didn’t contribute to PA or OA-induced KLF15 reduction.

Conclusions

Both PA and OA inhibit KLF15 expression through GPR120, leading to abnormal glucose metabolism in adipocytes. Notably, the inhibition of KLF15 expression by PA depends on phosphorylation of p38 MAPK.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-021-00628-2.

Identification of Key Pathways and Genes in Obesity Using Bioinformatics Analysis and Molecular Docking Studies

Obesity is an excess accumulation of body fat. Its progression rate has remained high in recent years. Therefore, the aim of this study was to diagnose important differentially expressed genes (DEGs) associated in its development, which may be used as novel biomarkers or potential therapeutic targets for obesity. The gene expression profile of E-MTAB-6728 was downloaded from the database. After screening DEGs in each ArrayExpress dataset, we further used the robust rank aggregation method to diagnose 876 significant DEGs including 438 up regulated and 438 down regulated genes. Functional enrichment analysis was performed. These DEGs were shown to be significantly enriched in different obesity related pathways and GO functions. Then protein-protein interaction network, target genes - miRNA regulatory network and target genes - TF regulatory network were constructed and analyzed. The module analysis was performed based on the whole PPI network. We finally filtered out STAT3, CORO1C, SERPINH1, MVP, ITGB5, PCM1, SIRT1, EEF1G, PTEN and RPS2 hub genes. Hub genes were validated by ICH analysis, receiver operating curve (ROC) analysis and RT-PCR. Finally a molecular docking study was performed to find small drug molecules. The robust DEGs linked with the development of obesity were screened through the expression profile, and integrated bioinformatics analysis was conducted. Our study provides reliable molecular biomarkers for screening and diagnosis, prognosis as well as novel therapeutic targets for obesity.

Knockdown of SNHG14 Alleviates MPP+-Induced Injury in the Cell Model of Parkinson's Disease by Targeting the miR-214-3p/KLF4 Axis

Background

Parkinson’s disease (PD) is the second most common neurodegenerative disease. Long non-coding RNA (lncRNA) small nucleolar RNA host gene 14 (SNHG14) has been demonstrated as an important regulator in PD pathology. However, the functional mechanisms played by SNHG14 in PD remain largely unclear.

Methods

We used 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 1-methyl-4-phenylpyridinium (MPP⁺) to establish PD mouse and cell models. The levels of SNHG14, miR-214-3p, and Krüppel-like factor 4 (KLF4) were gauged by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot analysis. Cell viability and apoptosis were determined using the Cell Counting-8 Kit (CCK-8) assay and flow cytometry, respectively. The levels of inflammatory cytokines were evaluated by ELISA. The relationships among SNHG14, miR-214-3p, and KLF4 were confirmed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays.

Results

Our data indicated that SNHG14 was upregulated and miR-214-3p was downregulated in PD models. SNHG14 knockdown ameliorated MPP⁺-stimulated damage in SK-N-SH cells, as evidenced by the enhancement in cell viability and the suppression in cell apoptosis and pro-inflammatory cytokine production. Mechanistically, SNHG14 directly targeted miR-214-3p via binding to miR-214-3p, and SNHG14 knockdown protected SK-N-SH cell from MPP⁺-stimulated cytotoxicity by upregulating miR-214-3p. KLF4 was a direct target of miR-214-3p, and SNHG14 regulated KLF4 expression by acting as a miR-214-3p sponge. Furthermore, miR-214-3p overexpression alleviated MPP⁺-stimulated damage in SK-N-SH cells by downregulating KLF4.

Conclusion

Our current study first demonstrated the protective effect of SNHG14 knockdown on MPP⁺-stimulated cytotoxicity in SK-N-SH cells at least partially by targeting the miR-214-3p/KLF4 axis, illuminating a promising target for PD intervention and treatment.

Saussureae Involucratae Herba (Snow Lotus): Review of Chemical Compositions and Pharmacological Properties

Saussureae Involucratae Herba is the dried ground part of Saussurea involucrata (Kar. et Kir.) Sch.-Bip, which is also named as “Snow lotus” and being used in traditional Uyghur and/or Chinese medicine. This rare herb can be found at 4,000 m elevation in western part of Tianshan Mountain, Xinjiang China. According to China Pharmacopoeia (2015), the major pharmaceutical values of “Snow lotus” (Xuě liánhuā in Chinese) are alleviating rheumatoid arthritis, accelerating blood circulation and mitigating other “cold” syndromes. Traditionally, the clinical application of “Snow lotus” includes the treatments in inflammation-associated disorder, blood circulation acceleration and heat and dampness elimination. Recent studies suggested that “Snow lotus” possessed therapeutic effects associating with anti-cancer, anti-oxidation, adipogenesis suppression and neuroprotection activities, which were proposed to be related with its bioactive constitutes, i.e. acacetin, hispidulin, and rutin. In the present review, we aim to summarize pharmacological effects and underlying cell signaling pathways of “Snow lotus” in treating various medical problems.

Sex differences in gene expression related to antipsychotic induced weight gain

Antipsychotics are crucial for the treatment of schizophrenia and contribute to weight gain in psychosis, particularly during early phases. Antipsychotic Induced Weight Gain (AIWG) might contribute to reduce the quality of life, drug compliance and to increase mortality. To characterize sex differences of gene expression related to AIWG, we sequenced total mRNA from blood samples of schizophrenia patients, before and after 3 months of antipsychotic-treatment. We analyzed schizophrenia patients according to their sex (38 males and 39 females) and their BMI increase after medication, characterizing the differential gene expression before and after medication. Individuals in each group were categorized in patients who gain weight and those whose do not gain weight. The “weight gain” groups included patients with an increase of body mass index (BMI) > 1.0 points (27 males and 23 females with a median BMI increase of 2.68 and 2.32 respectively). The “no weight gain” groups included patients with a change of BMI between < 1.0 and > -1.0 points (11 males and 16 females with a median BMI increase of 0.21 and 0.16 respectively). The males had 331 genes with significant differential expression in the weight gain group and 24 genes in the no weight gain group. The females had 119 genes with significant differential expression in the weight gain group and 75 genes in the no weight gain group. Both weight gain groups were significantly enriched with “obesity” genes (Fisher; p = 1.1E-09 and p = 0.0001 respectively), according to the Gene Reference into Function (GeneRIF) database.In conclusion, we characterized genes with differential expression associated to AIWG that are specific to males, to females and common to both sexes. These genes are good candidates to depict the biological processes involved in AIWG and provide additional evidence of the genetic links between weight gain and the immune system.

Different lipid profiles, insulin sensitivity, and insulin resistance among Han, Uygur, and Kazak men with normal glucose tolerance in Xinjiang, China

Background

This study aimed to determine the differences in clinical parameters among Han, Uygur, and Kazak men with normal glucose tolerance.

Methods

Participants’ data from the China National Diabetes and Metabolic Disorders Study pertaining to Han, Uygur, and Kazak men from the Xinjiang province were used (n = 930). Pearson’s correlation was used to examine the relationship between HOMA-IR, Matsuda Index, and clinical characteristics.

Results

HOMA-IR of Han men was significantly higher than in Uygurs and Kazaks (P < 0.001). The Matsuda Index of Kazaks was significantly higher than that of Hans and Uygurs (P < 0.001). While Kazaks had the highest BMI, WC, SBP, and DBP; they also had the highest HDL-C and lowest TG (P < 0.001). TG of Uygurs was significantly higher than that of Hans and Kazaks (P < 0.001). In Hans and Kazaks, the TG/HDL-C ratio increased with HOMA-IR quartiles; there was no association in Uygurs. In Hans and Kazaks, the TG/HDL-C ratio decreased with Matsuda index quartiles; there was no association in Uygurs. Multivariate linear regression showed that HOMA-IR was independently associated with ethnicity, BMI and TG/HDL-C ratio (P < 0.01), while Matsuda index was independently associated with ethnicity, BMI, LDL-C levels (P < 0.001) and TG/HDL-C ratio (P < 0.001).

Conclusions

In conclusion, Han, Uygur, and Kazak men had different lipid profiles, BMI, and WC. Han men had the highest insulin resistance while Kazak men had the highest insulin sensitivity.

Krüppel-like factor 4 expression in solid tumor prognosis: A meta-analysis

BACKGROUND

Accumulating studies have demonstrated that Krüppel-like factor 4 (KLF4) can act as a tumor suppressor or oncogene in the carcinogenesis of diverse cancers. The prognostic value of KLF4 in various human solid cancers remains controversial. Thus, the present meta-analysis was conducted to evaluate the prognostic value of KLF4 in solid tumors.

METHODS

Eligible literature was retrieved by searching the PubMed, Embase, and Cochrane Library. Combined hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS) were assessed using fixed-effects and random-effects models. Meta-regression and subgroup analyses were performed to identify the source of heterogeneity. In addition, publication bias was assessed using Begg's funnel plot and Egger's regression asymmetry test.

RESULTS

The 22 eligible studies finally enrolled a total of 2988 patients to assess the prognostic value of KLF4 in solid tumors. Low KLF4 expression was clearly related to worse OS (HR = 1.71, 95% confidence interval [CI] = 1.30-2.24, P < 0.001) and DFS (HR = 1.74, 95% CI = 1.34-2.26, P < 0.001), indicating that low KLF4 expression could be an independent prognostic factor for poor survival in solid cancers.

CONCLUSION

KLF4 might be a potential marker to predict prognosis in solid cancer patients.

Krüppel-like factors: Crippling and un-crippling metabolic pathways

Krüppel-like factors (KLFs) are DNA-binding transcriptional factors that regulate various pathways that control metabolism and other cellular mechanisms. Various KLF isoforms have been associated with cellular, organ or systemic metabolism. Altered expression or activation of KLFs has been linked to metabolic abnormalities, such as obesity and diabetes, as well as with heart failure. In this review article we summarize the metabolic functions of KLFs, as well as the networks of different KLF isoforms that jointly regulate metabolism in health and disease.