Exercise ameliorates high-fat diet-induced impairment of differentiation of adipose-derived stem cells into neuron-like cells in rats

Exercise training-driven exosomal miRNA-323-5p activity suppresses adipogenic conversion of 3T3-L1 cells via the DUSP3/ERK pathway

Adipose-derived stem cell (ASC)-released exosomes (ASCexos) have multiple biological activities. We examined the effect of ASCexos derived from the inguinal adipose tissue of exercise-trained rats (EX-ASCexos) on adipogenic conversion of 3T3-L1 cells and analyzed their microRNA (miRNA) expression profiles. Differentiation of 3T3-L1 cells into adipocytes was performed for 9 d with EX-ASCexos or ASCexos from sedentary control rats (SED-ASCexos), and the expression of proteins and miRNA involved in adipogenic differentiation were determined. EX-ASCexos but not SED-ASCexos attenuated 3T3-L1 adipocyte differentiation with increased phosph-Ser112PPARγ expression, the inactive form of PPARγ. These differentiated adipocytes were also accompanied by increased phosph-Thr202/Tyr204ERK and decreased dual-specificity phosphatase 3 (DUSP3) levels. The exosomal miRNAs miR-323-5p, miR-433-3p, and miR-874-3p were identified specifically in EX-ASCexos. Of these, miR-323-5p mimic replicated the EX-ASCexo-induced suppression of 3T3-L1 adipocyte differentiation and altered adipogenesis-related factor expression. In conclusion, exercise training-driven exosomal miR-323-5p suppressed 3T3-L1 adipogenesis by increasing phosph-Ser112PPARγ expression, while phosph-Thr202/Tyr204ERK accumulation inhibited DUSP3 expression.

Imeglimin Exhibits Novel Anti-Inflammatory Effects on High-Glucose-Stimulated Mouse Microglia through ULK1-Mediated Suppression of the TXNIP-NLRP3 Axis

Type 2 diabetes mellitus (T2DM) is an epidemiological risk factor for dementia and has been implicated in multifactorial pathologies, including neuroinflammation. In the present study, we aimed to elucidate the potential anti-inflammatory effects of imeglimin, a novel antidiabetic agent, on high-glucose (HG)-stimulated microglia. Mouse microglial BV2 cells were stimulated with HG in the presence or absence of imeglimin. We examined the effects of imeglimin on the levels of proinflammatory cytokines, intracellular reactive oxygen species (ROS), mitochondrial integrity, and components related to the inflammasome or autophagy pathways in these cells. Our results showed that imeglimin suppressed the HG-induced production of interleukin-1beta (IL-1β) by reducing the intracellular ROS levels, ameliorating mitochondrial dysfunction, and inhibiting the activation of the thioredoxin-interacting protein (TXNIP)-NOD-like receptor family pyrin domain containing 3 (NLRP3) axis. Moreover, the inhibitory effects of imeglimin on the TXNIP-NLRP3 axis depended on the imeglimin-induced activation of ULK1, which also exhibited novel anti-inflammatory effects without autophagy induction. These findings suggest that imeglimin exerted novel suppressive effects on HG-stimulated microglia through the ULK1-TXNIP-NLRP3 axis, and may, thereby, contribute to the development of innovative strategies to prevent T2DM-associated cognitive impairment.

Taxifolin Suppresses Inflammatory Responses of High-Glucose-Stimulated Mouse Microglia by Attenuating the TXNIP-NLRP3 Axis

Type 2 diabetes mellitus is associated with an increased risk of dementia, potentially through multifactorial pathologies, including neuroinflammation. Therefore, there is a need to identify novel agents that can suppress neuroinflammation and prevent cognitive impairment in diabetes. In the present study, we demonstrated that a high-glucose (HG) environment elevates the intracellular reactive oxygen species (ROS) levels and triggers inflammatory responses in the mouse microglial cell line BV-2. We further found that thioredoxin-interacting protein (TXNIP), a ROS-responsive positive regulator of the nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, was also upregulated, followed by NLRP3 inflammasome activation and subsequent interleukin-1beta (IL-1β) production in these cells. Conversely, caspase-1 was not significantly activated, suggesting the involvement of noncanonical pathways in these inflammatory responses. Moreover, our results demonstrated that taxifolin, a natural flavonoid with antioxidant and radical scavenging activities, suppressed IL-1β production by reducing the intracellular ROS levels and inhibiting the activation of the TXNIP-NLRP3 axis. These findings suggest the novel anti-inflammatory effects of taxifolin on microglia in an HG environment, which could help develop novel strategies for suppressing neuroinflammation in diabetes.

Reduction in endoplasmic reticulum stress activates beige adipocytes differentiation and alleviates high fat diet-induced metabolic phenotypes

Endoplasmic reticulum (ER) stress is closely associated with various metabolic diseases, such as obesity and diabetes. Development of beige/brite adipocytes increases thermogenesis and helps to reduce obesity. Although the relationship between ER stress and white adipocytes has been studied considerably, the possible role of ER stress and the unfolded protein response (UPR) induction in beige adipocytes differentiation remain to be investigated. In this study we investigated how ER stress affected beige adipocytes differentiation both in vitro and in vivo. Phosphorylation of eIF2α was transiently decreased in the early phase (day 2), whereas it was induced at the late phase with concomitant induction of C/EBP homologous protein (CHOP) during beige adipocytes differentiation. Forced expression of CHOP inhibited the expression of beige adipocytes markers, including Ucp1, Cox8b, Cidea, Prdm16, and Pgc-1α, following the induction of beige adipocytes differentiation. When ER stress was reduced by the chemical chaperone tauroursodeoxycholic acid (TUDCA), the expression of the beige adipocytes marker uncoupling protein 1 (UCP1) was significantly enhanced in inguinal white adipose tissue (iWAT) and high fat diet (HFD)-induced abnormal metabolic phenotype was improved. In summary, we found that ER stress and the UPR induction were closely involved in beige adipogenesis. These results suggest that modulating ER stress could be a potential therapeutic intervention against metabolic dysfunctions via activation of iWAT browning.

Metabolomic Profiles in Adipocytes Differentiated from Adipose-Derived Stem Cells Following Exercise Training or High-Fat Diet

Controlling the differentiation potential of adipose-derived stem cells (ADSCs) is attracting attention as a new strategy for the prevention and treatment of obesity. Here, we aimed to observe the effect of exercise training (TR) and high-fat diet (HFD) on the metabolic profiles of ADSCs-derived adipocytes. The rats were divided into four groups: normal diet (ND)-fed control (ND-SED), ND-fed TR (ND-TR), HFD-fed control (HFD-SED), and HFD-fed TR (HFD-TR). After 9 weeks of intervention, ADSCs of epididymal and inguinal adipose tissues were differentiated into adipocytes. In the metabolome analysis of adipocytes after isoproterenol stimulation, 116 metabolites were detected. The principal component analysis demonstrated that ADSCs-derived adipocytes segregated into four clusters in each fat pad. Amino acid accumulation was greater in epididymal ADSCs-derived adipocytes of ND-TR and HFD-TR, but lower in inguinal ADSCs-derived adipocytes of ND-TR, than in the respective controls. HFD accumulated several metabolites including amino acids in inguinal ADSCs-derived adipocytes and more other metabolites in epididymal ones. Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that TR mainly affected the pathways related to amino acid metabolism, except in inguinal ADSCs-derived adipocytes of HFD-TR rats. These findings provide a new way to understand the mechanisms underlying possible changes in the differentiation of ADSCs due to TR or HFD.

Executive Function and Diabetes: A Clinical Neuropsychology Perspective

Objective

Diabetes is a global public health concern. Management of diabetes depends on successful implementation of strategies to alleviate decline in executive functions (EFs), a characteristic of diabetes progression. In this review, we describe recent research on the relationship between diabetes and EF, summarize the existing evidence, and put forward future research directions and applications.

Methods

Herein, we provide an overview of recent studies, to elucidate the relationship between DM and EF. We identified new screening objectives, management tools, and intervention targets for diabetes management. We also discuss the implications for clinical practice.

Results

In both types 1 and 2 diabetes mellitus (DM), hyperglycemia substantially impairs EF in people of all age groups and ethnicities. Hypoglycemia can similarly impair EF. Interestingly, a decline in EF contributes to DM progression. Glucose dysregulation and EF decline exacerbate each other in a vicious cycle: poor blood glucose control, impaired EF, diabetes management task failure, then back to poor blood glucose control. Many pathophysiological indexes (e.g., obesity, metabolic index, inflammatory and immune factors), neuropsychological indexes (e.g., compliance, eating habits, physical exercise, sleep, and depression), and genetic factors are changed by this pathological interaction between DM and EF. These changes can provide insight into the pathophysiological mechanisms of diabetes-related EF decline.

Conclusion

Further studies, including large-scale prospective and randomized controlled trials, are needed to elucidate the mechanism of the interaction between diabetes and EF and to develop novel strategies for breaking this cycle.

Fat graft for reducing pain in chronic wounds

BACKGROUND

Chronic wounds are one of the most important challenge for regenerative surgery. Plastic surgeon can use fat graft to increase wound healing because its growth factors can enhance tissue regeneration. In a recent study, the authors evaluated a reduction of pain in a cohort of patients submitted to breast reconstruction with breast implant and lipofilling, putting into evidence that growth factors in fat graft can reduce post-surgical pain. The aim of this work is to evaluate ultra-filtered fat graft potential in reducing pain in chronic wounds.

PATIENTS AND METHODS

Fifty new patients with chronic wounds of different etiology were recruited for this study and divided into two groups: A, treatment and B, control. Twenty-five patients per group. Negative pressure therapy dressing was applied after surgical debridement. Three days later patients in group A received ultrafiltered fat graft. Pain was evaluated with preoperative Visual Analogic Scale, repeated twice a day for 14 days and finally 21 days from procedures.

RESULTS

In group A (treated patients), pain was lower. These data were confirmed even after 7 days. The overall statistical analysis of the average of all values (SD 1.72) confirmed that the differences were significant at the 95% with the Chi-square test and analysis of variance (P value < .05).

CONCLUSIONS

The ultra-filtered fat graft placed on the wound bed and edges was effective in reducing pain in chronic wounds. The reduction of pain was statistically significant.

Neural-like cells from adipose-derived stem cells for cavernous nerve injury in rats

Although the remaining nerve tissue can regenerate and partly restore erectile function when the cavernous nerve is compressed/severed and function lost, the limited regenerative ability of these nerve tissues often fails to meet clinical needs. Adipose-derived stem cells are easy to obtain and culture, and can differentiate into neural cells. Their proliferation rate is easy to control and they may be used to help restore injured cavernous nerve function. Sprague-Dawley male rats (n = 45) were equally randomized into three groups: fifteen rats as a sham-operated group, fifteen rats as a bilateral nerve crush (BINC) group (with no further intervention), fifteen rats as a BINC with intracavernous injection of one million neural-like cells from adipose-derived stem cells (NAS) (BINC + NAS) group. After 4 weeks, erectile function was assessed by stimulating the cavernous body. The number of myelinated axons in the dorsal cavernous nerve was determined by toluidine blue staining. The area of neuronal nitric oxide synthase-positive fibers in the dorsal penile nerve was measured by immunohistochemical staining. Masson staining was used to analyze the ratio of smooth muscle to collagen in penile tissue. The results demonstrate that maximal intracavernous pressure, the ratio of maximal intracavernous pressure to mean arterial pressure, the numbers of myelinated axons and neuronal nitric oxide synthase-positive fibers in the dorsal penile nerve, and the ratio of smooth muscle to collagen could be increased after cell transplantation. These findings indicate that neural-like cells from adipose-derived stem cells can effectively alleviate cavernous nerve injury and improve erectile function. All animal experiments were approved by the Animal Ethics Committee of Huazhong University of Science and Technology, China (approval No. 2017-1925) on September 15, 2017.

Adipose Stem Cell Translational Applications: From Bench-to-Bedside

During the last five years, there has been a significantly increasing interest in adult adipose stem cells (ASCs) as a suitable tool for translational medicine applications. The abundant and renewable source of ASCs and the relatively simple procedure for cell isolation are only some of the reasons for this success. Here, we document the advances in the biology and in the innovative biotechnological applications of ASCs. We discuss how the multipotential property boosts ASCs toward mesenchymal and non-mesenchymal differentiation cell lineages and how their character is maintained even if they are combined with gene delivery systems and/or biomaterials, both in vitro and in vivo.