A programmable protease-based protein secretion platform for therapeutic applications.

Cell-based therapies represent potent enabling technologies in biomedical science. However, current genetic control systems for engineered-cell therapies are predominantly based on the transcription or translation of therapeutic outputs. Here we report a protease-based rapid protein secretion system (PASS) that regulates the secretion of pretranslated proteins retained in the endoplasmic reticulum (ER) owing to an ER-retrieval signal. Upon cleavage by inducible proteases, these proteins are secreted. Three PASS variants (chemPASS, antigenPASS and optoPASS) are developed. With chemPASS, we demonstrate the reversal of hyperglycemia in diabetic mice within minutes via drug-induced insulin secretion. AntigenPASS-equipped cells recognize the tumor antigen and secrete granzyme B and perforin, inducing targeted cell apoptosis. Finally, results from mouse models of diabetes, hypertension and inflammatory pain demonstrate light-induced, optoPASS-mediated therapeutic peptide secretion within minutes, conferring anticipated therapeutic benefits. PASS is a flexible platform for rapid delivery of therapeutic proteins that can facilitate the development and adoption of cell-based precision therapies.

Controlling therapeutic protein expression via inhalation of a butter flavor molecule.

Precise control of the delivery of therapeutic proteins is critical for gene- and cell-based therapies, and expression should only be switched on in the presence of a specific trigger signal of appropriate magnitude. Focusing on the advantages of delivering the trigger by inhalation, we have developed a mammalian synthetic gene switch that enables regulation of transgene expression by exposure to the semi-volatile small molecule acetoin, a widely used, FDA-approved food flavor additive. The gene switch capitalizes on the bacterial regulatory protein AcoR fused to a mammalian transactivation domain, which binds to promoter regions with specific DNA sequences in the presence of acetoin and dose-dependently activates expression of downstream transgenes. Wild-type mice implanted with alginate-encapsulated cells transgenic for the acetoin gene switch showed a dose-dependent increase in blood levels of reporter protein in response to either administration of acetoin solution via oral gavage or longer exposure to acetoin aerosol generated by a commercial portable inhaler. Intake of typical acetoin-containing foods, such as butter, lychees and cheese, did not activate transgene expression. As a proof of concept, we show that blood glucose levels were normalized by acetoin aerosol inhalation in type-I diabetic mice implanted with acetoin-responsive insulin-producing cells. Delivery of trigger molecules using portable inhalers may facilitate regular administration of therapeutic proteins via next-generation cell-based therapies to treat chronic diseases for which frequent dosing is required.

Exercise training and spexin ameliorate thyroid changes in obese type 2 diabetic rats: the possible interlaying mechanisms.

Thyroid dysfunction and diabetes mellitus are prevalent endocrine disorders that often coexist and influence each other. The role of spexin (SPX) in diabetes and obesity is well documented, but its connection to thyroid function is less understood. This study investigates the influence of exercise (EX) and SPX on thyroid hypofunction in obese type 2 diabetic rats. Rats were divided into normal control, obese diabetic sedentary, obese diabetic EX, and obese diabetic SPX groups, with subdivisions for M871 and HT-2157 treatment in the latter two groups. High-fat diet together with streptozotocin (STZ) injection induced obesity and diabetes. The EX group underwent swimming, and the SPX group received SPX injections for 8 wk. Results showed significant improvements in thyroid function and metabolic, oxidative, and inflammatory states with EX and SPX treatment. The study also explored the involvement of galanin receptor isoforms (GALR)2/3 in SPX effects on thyroid function. Blocking GALR2/3 receptors partially attenuated the beneficial effects, indicating their interaction. These findings underscore the importance of EX and SPX in modulating thyroid function in obesity and diabetes. Comprehending this interplay could enable the development of new treatment approaches for thyroid disorders associated with obese type 2 diabetes. Additional research is necessary to clarify the exact mechanisms connecting SPX, EX activity, and thyroid function.NEW & NOTEWORTHY This study proves, for the first time, the beneficial effects of SPX on thyroid dysfunction in obese diabetic rats and suggests that SPX mediates the EX effect on thyroid gland and exerts its effect mainly via GALR2.

The analysis of the skeletal muscle metabolism is crucial for designing optimal exercise paradigms in type 2 diabetes mellitus.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease that commonly results from a high-calorie diet and sedentary lifestyle, leading to insulin resistance and glucose homeostasis perturbation. Physical activity is recommended as one first-line treatment in T2DM, but it leads to contrasted results. We hypothesized that, instead of applying standard exercise protocols, the prescription of personalized exercise programs specifically designed to reverse the potential metabolic alterations in skeletal muscle could result in better results. METHODS: To test this hypothesis, we drew the metabolic signature of the fast-twitch quadriceps muscle, based on a combined unbiased NMR spectroscopy and RT-qPCR study, in several T2DM mouse models of different genetic background (129S1/SvImJ, C57Bl/6J), sex and aetiology (high-fat diet (HFD) or HFD/Streptozotocin (STZ) induction or transgenic MKR (FVB-Tg Ckm-IGF1R*K1003R)1Dlr/J) mice. Three selected mouse models with unique muscular metabolic signatures were submitted to three different swimming-based programs, designed to address each metabolic specificity. RESULTS: We found that depending on the genetic background, the sex, and the mode of T2DM induction, specific muscular adaptations occurred, including depressed glycolysis associated with elevated PDK4 expression, shift to ß-oxidation, or deregulation of amino-acid homeostasis. Interestingly, dedicated swimming-based exercises designed to restore specific metabolic alterations in muscle were found optimal in improving systemic T2DM hallmarks, including a significant reduction in insulin resistance, the improvement of glucose homeostasis, and a delay in sensorimotor function alterations. CONCLUSION: The muscle metabolism constitutes an important clue for the design of precision exercises with potential clinical implications for T2DM patients.

Mesenchymal Stem Cell-Derived Exosomes Ameliorate Diabetic Kidney Disease Through the NLRP3 Signaling Pathway.

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease worldwide. Exosomes (Exo) derived from human umbilical cord mesenchymal stem cells (HUC-MSCs) have been demonstrated to be an effective therapy for DKD, but the underlying mechanisms of this action remain poorly defined. We investigated the association of DKD with inflammasome activation and the pathophysiological relevance of Exo-mediated inflammation relief as well as damage repair in this progression. We co-cultured podocytes and HUC-MSCs derived Exo (MSCs-Exo) under high glucose (HG) and injected MSCs-Exo into diabetic mice, then we detected the NLRP3 inflammasome both in vitro and in vivo. We found that HG reduced the viability of podocytes, activated the NLRP3 signaling pathway and increased inflammation in podocytes and diabetic mice. MSCs-Exo attenuated the inflammation, including the expression of IL-6, IL-1ß, IL-18, TNF-α; depressed the activation of NLRP3 signaling pathway in podocytes under HG and diabetic mice, ameliorated kidney injury. Furthermore, miR-22-3p, which is relatively highly expressed miRNAs in exosomes of MSCs, may be the key point in this progress, by suppressing the expression of its known target, NLRP3. Knocking down miR-22-3p from MSCs-Exo abolished their anti-inflammation activity and beneficial function both in vitro and in vivo. Collectively, our results have demonstrated that exosomes transferring miR-22-3p protected the podocytes and diabetic mice from inflammation by mediating NLRP3 inflammasome, indicating that MSC-derived exosomes may be a promising therapeutic cell-free strategy for DKD.

Translational application of human keratinocyte-fibroblast cell sheets for accelerated wound healing in a clinically relevant type 2 diabetic rat model.

BACKGROUND AIMS: Despite advancements in wound care, wound healing remains a challenge, especially in individuals with type 2 diabetes. Cell sheet technology has emerged as an efficient and promising therapy for tissue regeneration and wound repair. Among these, bilayered human keratinocyte-fibroblast cell sheets constructed using temperature-responsive culture surfaces have been shown to mimic a normal tissue-like structure and secrete essential cytokines and growth factors that regulate the wound healing process. METHODS: This study aimed to evaluate the safety and therapeutic potential of human skin cell sheets to treat full-thickness skin defects in a rat model of type 2 diabetes. RESULTS: Our findings demonstrate that diabetic wounds transplanted with bilayered cell sheets resulted in accelerated re-epithelialization, increased angiogenesis, enhanced macrophage polarization and regeneration of tissue that closely resembled healthy skin. In contrast, the control group that did not receive cell sheet transplantation presented characteristic symptoms of impaired and delayed wound healing associated with type 2 diabetes. CONCLUSIONS: The secretory cytokines and the upregulation of Nrf2 expression in response to cell sheet transplantation are believed to have played a key role in the improved wound healing observed in diabetic rats. Our study suggests that human keratinocyte-fibroblast cell sheets hold great potential as a therapeutic alternative for diabetic ulcers.

Clinical-grade human embryonic stem cell-derived mesenchymal stromal cells ameliorate diabetic retinopathy in db/db mice.

BACKGROUND AIMS: Mesenchymal stromal cells (MSCs) hold great promise in the treatment of diabetic retinopathy (DR), as evidenced by increasing preclinical and clinical studies. However, the absence of standardized and industrialized clinical-grade donor cells hampers the continued development and large-scale clinical application of MSCs-based therapies for DR. Previously, we have identified a unique population of MSCs generated from a clinical-grade human embryonic stem cell (hESC) line under Good Manufacturing Practice conditions that could be a potential source to address the issues. Here, we investigated the therapeutic potential of the clinical-grade hESC line-derived MSCs (hESC-MSCs) on db/db mice with DR. METHODS: hESC-MSCs were initially characterized by morphological assessment, flow cytometry analysis and trilineage differentiation assays. These cells (5 × 106 cells) were then transplanted intravenously into 12-week-old db/db mice via tail vein, with phosphate-buffered saline transplantation and untreated groups used as controls. The retinal alterations in neural functions and microvascular perfusions, and inflammatory responses in peripheral blood and retina were evaluated at 4 and 6 weeks after transplantation using electroretinography, optical coherence tomography angiography and flow cytometry, respectively. Body weight and fasting blood glucose (FBG) levels were also measured to investigate their systemic implications. RESULTS: Compared with controls, intravenous transplantation of hESC-MSCs could significantly: (i) enhance impaired retinal electroretinography functions (including amplitudes of a-, b-wave and oscillatory potentials) at 4 weeks after transplantation; (ii) alleviate microvascular dysfunctions, especially in the inner retina with significance (including reducing non-perfusion area and increasing vascular area density) at 4 weeks after transplantation; (iii) decrease FBG levels at 4 weeks after transplantation and induce weight loss up to 6 weeks after transplantation and (iv) increase both peripheral blood and retinal interleukin-10 levels at 4 weeks after transplantation and modulate peripheral blood inflammatory cytokines and chemokines levels, such as monocyte chemotactic protein-1, up to 6 weeks after transplantation. CONCLUSIONS: The findings of our study indicated that intravenous transplantation of hESC-MSCs ameliorated retinal neural and microvascular dysfunctions, regulated body weight and FBG and modulated peripheral blood and retinal inflammation responses in a mouse model of DR. These results suggest that hESC-MSCs could be a potentially effective clinical-grade cell source for the treatment of DR.

Genetic-code-expanded cell-based therapy for treating diabetes in mice.

Inducer-triggered therapeutic protein expression from designer cells is a promising strategy for disease treatment. However, as most inducer systems harness transcriptional machineries, protein expression timeframes are unsuitable for many therapeutic applications. Here, we engineered a genetic code expansion-based therapeutic system, termed noncanonical amino acids (ncAAs)-triggered therapeutic switch (NATS), to achieve fast therapeutic protein expression in response to cognate ncAAs at the translational level. The NATS system showed response within 2 hours of triggering, whereas no signal was detected in a transcription-machinery-based system. Moreover, NATS system is compatible with transcriptional switches for multi-regulatory-layer control. Diabetic mice with microencapsulated cell implants harboring the NATS system could alleviate hyperglycemia within 90 min on oral delivery of ncAA. We also prepared ncAA-containing 'cookies' and achieved long-term glycemic control in diabetic mice implanted with NATS cells. Our proof-of-concept study demonstrates the use of NATS system for the design of next-generation cell-based therapies to achieve fast orally induced protein expression.

A static magnetic field improves bone quality and balances the function of bone cells with regulation on iron metabolism and redox status in type 1 diabetes.

Osteoporosis is one of the chronic complications of type 1 diabetes with high risk of fracture. The prevention of diabetic osteoporosis is of particular importance. Static magnetic fields (SMFs) exhibit advantages on improvement of diabetic complications. The biological effects and mechanism of SMFs on bone health of type 1 diabetic mice and functions of bone cells under high glucose have not been clearly clarified. In animal experiment, six-week-old male C57BL/6J mice were induced to type 1 diabetes and exposed to SMF of 0.4-0.7 T for 4 h/day lasting for 6 weeks. Bone mass, biomechanical strength, microarchitecture and metabolism were determined by DXA, three-point bending assay, micro-CT, histochemical and biochemical methods. Exposure to SMF increased BMD and BMC of femur, improved biomechanical strength with higher ultimate stress, stiffness and elastic modulus, and ameliorated the impaired bone microarchitecture in type 1 diabetic mice by decreasing Tb.Pf, Ct.Po and increasing Ct.Th. SMF enhanced bone turnover by increasing the level of markers for bone formation (OCN and Collagen I) as well as bone resorption (CTSK and NFAT2). In cellular experiment, MC3T3-E1 cells or primary osteoblasts and RAW264.7 cells were cultured in 25 mM high glucose-stimulated diabetic marrow microenvironment under differentiation induction and exposed to SMF. SMF promoted osteogenesis with higher ALP level and mineralization deposition in osteoblasts, and it also enhanced osteoclastogenesis with higher TRAP activity and bone resorption in osteoclasts under high glucose condition. Further, SMF increased iron content with higher FTH1 expression and regulated the redox level through activating HO-1/Nrf2 in tibial tissues, and lowered hepatic iron accumulation by BMP6-mediated regulation of hepcidin and lipid peroxidation in mice with type 1 diabetes. Thus, SMF may act as a potential therapy for improving bone health in type 1 diabetes with regulation on iron homeostasis metabolism and redox status.

Insulin-Induced Gene 1-Enhance Secretion of BMSC Exosome Enriched in miR-132-3p Promoting Wound Healing in Diabetic Mice.

Chronic diabetic wounds represent a significant clinical challenge because of impaired healing processes, which require innovative therapeutic strategies. This study explores the therapeutic efficacy of insulin-induced gene 1-induced bone marrow mesenchymal stem cell exosomes (Insig1-exos) in promoting wound healing in diabetic mice. We demonstrated that Insig1 enhanced the secretion of bone marrow mesenchymal stem cell-derived exosomes, which are enriched with miR-132-3p. Through a series of in vitro and in vivo experiments, these exosomes significantly promoted the proliferation, migration, and angiogenesis of dermal fibroblasts under high-glucose conditions. They also regulated key wound-healing factors, including matrix metalloproteinase-9, platelet-derived growth factor, vascular endothelial growth factor, transforming growth factor-ß1, and platelet endothelial cell adhesion molecule-1, thereby accelerating wound closure in diabetic mice. Histological analysis showed that Insig1-exos were more effective in promoting epithelialization, enhancing collagen deposition, and reducing inflammation. Additionally, inhibition of miR-132-3p notably diminished these therapeutic effects, underscoring its pivotal role in the wound-healing mechanism facilitated by Insig1-exos. This study elucidates the molecular mechanisms through which Insig1-exos promotes diabetic wound healing, highlighting miR-132-3p as a key mediator. These findings provide new strategies and theoretical foundations for treating diabetes-related skin injuries.

Changes in the hippocampal level of tau but not beta-amyloid may mediate anxiety-like behavior improvement ensuing from exercise in diabetic female rats.

BACKGROUND: In the present study, we investigated the effect of high-intensity interval training (HIIT) on cognitive behaviors in female rats with a high-fat diet + streptozotocin (STZ)-induced type 2 diabetes. METHODS: Twenty-four female rats were divided into four groups randomly (n = 6): control (C), control + exercise (Co + EX), diabetes mellitus (type 2) (T2D), and diabetes mellitus + exercise (T2D + EX). Diabetes was induced by a two-month high-fat diet and a single dose of STZ (35 mg/kg) in the T2D and T2D + EX groups. The Co + EX and T2D + EX groups performed HIIT for eight weeks (five sessions per week, running on a treadmill at 80-100% of VMax, 4-10 intervals). Elevated plus maze (EPM) and open field test (OFT) were used for assessing anxiety-like behaviors, and passive avoidance test (PAT) and Morris water maze (MWM) were applied for evaluating learning and memory. The hippocampal levels of beta-amyloid (Aß) and Tau were also assessed using Western blot. RESULTS: An increase in fasting blood glucose (FBG), hippocampal level of Tau, and a decrease in the percentage of open arm time (%OAT) as an index of anxiety-like behavior were seen in the female diabetic rats which could be reversed by HIIT. In addition, T2D led to a significant decrease in rearing and grooming in the OFT. No significant difference among groups was seen for the latency time in the PAT and learning and memory in the MWM. CONCLUSIONS: HIIT could improve anxiety-like behavior at least in part through changes in hippocampal levels of Tau.

Genetic analysis of impaired healing responses after periodontal therapy in type 2 diabetes: Clinical and in vivo studies.

OBJECTIVE: This study aims to investigate the mechanisms underlying the impaired healing response by diabetes after periodontal therapy. BACKGROUND: Outcomes of periodontal therapy in patients with diabetes are impaired compared with those in patients without diabetes. However, the mechanisms underlying impaired healing response to periodontal therapy have not been sufficiently investigated. MATERIALS AND METHODS: Zucker diabetic fatty (ZDF) and lean (ZL) rats underwent experimental periodontitis by ligating the mandibular molars for one week. The gingiva at the ligated sites was harvested one day after ligature removal, and gene expression was comprehensively analyzed using RNA-Seq. In patients with and without type 2 diabetes (T2D), the corresponding gene expression was quantified in the gingiva of the shallow sulcus and residual periodontal pocket after non-surgical periodontal therapy. RESULTS: Ligation-induced bone resorption and its recovery after ligature removal were significantly impaired in the ZDF group than in the ZL group. The RNA-Seq analysis revealed 252 differentially expressed genes. Pathway analysis demonstrated the enrichment of downregulated genes involved in the peroxisome proliferator-activated receptor (PPAR) signaling pathway. PPARα and PPARγ were decreased in mRNA level and immunohistochemistry in the ZDF group than in the ZL group. In clinical, probing depth reduction was significantly less in the T2D group than control. Significantly downregulated expression of PPARα and PPARγ were detected in the residual periodontal pocket of the T2D group compared with those of the control group, but not in the shallow sulcus between the groups. CONCLUSIONS: Downregulated PPAR subtypes expression may involve the impaired healing of periodontal tissues by diabetes.

Electroacupuncture modulates the TLR4-NF-κB inflammatory signaling pathway to attenuate ocular surface inflammation in dry eyes of type 2 diabetic rats.

Bioinformatics analysis was performed to reveal the underlying pathogenesis of type 2 diabetes (T2DM) dry eye(DE) and to predict the core targets and potential pathways for electroacupuncture (EA) treatment of T2DM DE, in which key targets such as Toll-likereceptor4 (TLR4), NF-κB and Tumor necrosis factor-α (TNF-α) may be involved. Next, streptozotocin and a high-fat diet were used to generate T2DM-DE rats. Randomly picked EA, fluorometholone, model, and sham EA groups were created from successfully modelled T2DM DE rats. Six more rats were chosen as the blank group from among the normal rats. The results of DE index showed that EA improved the ocular surface symptoms.HE staining showed that EA attenuated the pathological changes in the cornea, conjunctiva and lacrimal gland of T2DM DE rats. EA decreased the expression of TLR4, MyD88, P-NF-κB P65, and TNF-α in the cornea, conjunctiva, and lacrimal gland, in accordance with immunofluorescence and Western blot data. Thus, EA reduced ocular surface symptoms and improved pathological changes of cornea, conjunctiva, and lacrimal gland induced by T2DM DE inT2DM DE rats, and the mechanism may be related to the inhibition of overactivation of the TLR4/NF-κB signaling pathway by EA and thus attenuating ocular surface inflammation.

Light-stimulated insulin secretion from pancreatic islet-like organoids derived from human pluripotent stem cells.

Optogenetic techniques permit non-invasive, spatiotemporal, and reversible modulation of cellular activities. Here, we report a novel optogenetic regulatory system for insulin secretion in human pluripotent stem cell (hPSC)-derived pancreatic islet-like organoids using monSTIM1 (monster-opto-Stromal interaction molecule 1), an ultra-light-sensitive OptoSTIM1 variant. The monSTIM1 transgene was incorporated at the AAVS1 locus in human embryonic stem cells (hESCs) by CRISPR-Cas9-mediated genome editing. Not only were we able to elicit light-induced intracellular Ca2+ concentration ([Ca2+]i) transients from the resulting homozygous monSTIM1+/+-hESCs, but we also successfully differentiated them into pancreatic islet-like organoids (PIOs). Upon light stimulation, the ß-cells in these monSTIM1+/+-PIOs displayed reversible and reproducible [Ca2+]i transient dynamics. Furthermore, in response to photoexcitation, they secreted human insulin. Light-responsive insulin secretion was similarly observed in monSTIM1+/+-PIOs produced from neonatal diabetes (ND) patient-derived induced pluripotent stem cells (iPSCs). Under LED illumination, monSTIM1+/+-PIO-transplanted diabetic mice produced human c-peptide. Collectively, we developed a cellular model for the optogenetic control of insulin secretion using hPSCs, with the potential to be applied to the amelioration of hyperglycemic disorders.

NIR-responsive electrospun nanofiber dressing promotes diabetic-infected wound healing with programmed combined temperature-coordinated photothermal therapy.

BACKGROUND: Diabetic wounds present significant challenges, specifically in terms of bacterial infection and delayed healing. Therefore, it is crucial to address local bacterial issues and promote accelerated wound healing. In this investigation, we utilized electrospinning to fabricate microgel/nanofiber membranes encapsulating MXene-encapsulated microgels and chitosan/gelatin polymers. RESULTS: The film dressing facilitates programmed photothermal therapy (PPT) and mild photothermal therapy (MPTT) under near-infrared (NIR), showcasing swift and extensive antibacterial and biofilm-disrupting capabilities. The PPT effect achieves prompt sterilization within 5 min at 52 °C and disperses mature biofilm within 10 min. Concurrently, by adjusting the NIR power to induce local mild heating (42 °C), the dressing stimulates fibroblast proliferation and migration, significantly enhancing vascularization. Moreover, in vivo experimentation successfully validates the film dressing, underscoring its immense potential in addressing the intricacies of diabetic wounds. CONCLUSIONS: The MXene microgel-loaded nanofiber dressing employs temperature-coordinated photothermal therapy, effectively amalgamating the advantageous features of high-temperature sterilization and low-temperature promotion of wound healing. It exhibits rapid, broad-spectrum antibacterial and biofilm-disrupting capabilities, exceptional biocompatibility, and noteworthy effects on promoting cell proliferation and vascularization. These results affirm the efficacy of our nanofiber dressing, highlighting its significant potential in addressing the challenge of diabetic wounds struggling to heal due to infection.

The effect of diabetes mellitus on differentiation of mesenchymal stem cells into insulin-producing cells.

BACKGROUND: Diabetes mellitus (DM) is a global epidemic with increasing incidences. DM is a metabolic disease associated with chronic hyperglycemia. Aside from conventional treatments, there is no clinically approved cure for DM up till now. Differentiating mesenchymal stem cells (MSCs) into insulin-producing cells (IPCs) is a promising approach for curing DM. Our study was conducted to investigate the effect of DM on MSCs differentiation into IPCs in vivo and in vitro. METHODS: We isolated adipose-derived mesenchymal stem cells (Ad-MSCs) from the epididymal fat of normal and STZ-induced diabetic Sprague-Dawley male rats. Afterwards, the in vitro differentiation of normal-Ad-MSCs (N-Ad-MSCs) and diabetic-Ad-MSCs (DM-Ad-MSCs) into IPCs was compared morphologically then through determining the gene expression of ß-cell markers including neurogenin-3 (Ngn-3), homeobox protein (Nkx6.1), musculoaponeurotic fibrosarcoma oncogene homolog A (MafA), and insulin-1 (Ins-1) and eventually, through performing glucose-stimulated insulin secretion test (GSIS). Finally, the therapeutic potential of N-Ad-MSCs and DM-Ad-MSCs transplantation was compared in vivo in STZ-induced diabetic animals. RESULTS: Our results showed no significant difference in the characteristics of N-Ad-MSCs and DM-Ad-MSCs. However, we demonstrated a significant difference in their abilities to differentiate into IPCs in vitro morphologically in addition to ß-cell markers expression, and functional assessment via GSIS test. Furthermore, the abilities of both Ad-MSCs to control hyperglycemia in diabetic rats in vivo was assessed through measuring fasting blood glucose (FBGs), body weight (BW), histopathological examination of both pancreas and liver and immunoexpression of insulin in pancreata of study groups. CONCLUSION: Our findings reveal the effectiveness of N-Ad-MSCs in differentiating into IPCs in vitro and controlling the hyperglycemia of STZ-induced diabetic rats in vivo compared to DM-Ad-MSCs.

Lung molecular and histological changes in type 2 diabetic rats and its improvement by high-intensity interval training.

BACKGROUND: Type 2 diabetes (T2D) leads to serious respiratory problems. This study investigated the effectiveness of high-intensity interval training (HIIT) on T2D-induced lung injuries at histopathological and molecular levels. METHODS: Forty-eight male Wistar rats were randomly allocated into control (CTL), Diabetes (Db), exercise (Ex), and Diabetes + exercise (Db + Ex) groups. T2D was induced by a high-fat diet plus (35 mg/kg) of streptozotocin (STZ) administration. Rats in Ex and Db + Ex performed HIIT for eight weeks. Tumor necrosis factor-alpha (TNFα), Interleukin 10 (IL-10), BAX, Bcl2, Lecithin, Sphingomyelin (SPM) and Surfactant protein D (SPD) levels were measured in the bronchoalveolar lavage fluid (BALF) and malondialdehyde (MDA) and total antioxidant capacity (TAC) levels were measured in lung tissue. Lung histopathological alterations were assessed by using H&E and trichrome mason staining. RESULTS: Diabetes was significantly associated with imbalance in pro/anti-inflammatory, pro/anti-apoptosis and redox systems, and reduced the SPD, lecithin sphingomyelin and alveolar number. Performing HIIT by diabetic animals increased Bcl2 (P < 0.05) and IL10 (P < 0.01) levels as well as surfactants components and TAC (P < 0.05) but decreased fasting blood glucose (P < 0.001), TNFα (P < 0.05), BAX (P < 0.05) and BAX/Bcl2 (P < 0.001) levels as well as MDA (P < 0.01) and MDA/TAC (P < 0.01) compared to the diabetic group. Furthermore, lung injury and fibrosis scores were increased by T2D and recovered in presence of HIIT. CONCLUSION: These findings suggested that the attenuating effect of HIIT on diabetic lung injury mediated by reducing blood sugar, inflammation, oxidative stress, and apoptosis as well as improving pulmonary surfactants components.

Inhibition of Th17 cell differentiation by aerobic exercise improves vasodilatation in diabetic mice.

BACKGROUND: Aortic endothelial diastolic dysfunction is an early complication of diabetes and the abnormal differentiation of Th17 cells is involved in the development of diabetes. However, the exact role of exercise on regulating the Th17 cells differentiation and the underlying molecular mechanisms remain to be elucidated in diabetic mice. METHODS: db/db and db/m+ mice were randomly divided into exercise and sedentary groups. Mice in exercise group were exercised daily, 6 days/week, for 6 weeks and mice in sedentary groups were placed on a nonmoving treadmill for 6 weeks. Vascular endothelial function was measured via wire myograph and the frequencies of Th17 from peripheral blood in mice were assessed via flow cytometry. RESULTS: Our data showed that exercise improved insulin resistance and aortic endothelial diastolic function in db/db mice. In addition, the proportion of Th17 cells and IL-17A level in peripheral blood of db/db mice were significantly increased, and exercise could promote Th17 cell differentiation and reduce IL-17A level. More importantly, STAT3 or ROR-γt inhibitors could promote Th17 cell differentiation in db/db mice, while exercise significantly down-regulated p-STAT3/ROR-γt signaling in db/db mice, suggesting that exercise regulated Th17 differentiation through STAT3/ROR-γt signaling. CONCLUSIONS: This study demonstrated that exercise improved vascular endothelial function in diabetic mice via reducing Th17 cell differentiation through p-STAT3/ROR-γt pathway, suggesting exercise may be an important non-pharmacological intervention strategy for the treatment of diabetes-related vascular complications.

Glucagon blockade restores functional ß-cell mass in type 1 diabetic mice and enhances function of human islets.

We evaluated the potential for a monoclonal antibody antagonist of the glucagon receptor (Ab-4) to maintain glucose homeostasis in type 1 diabetic rodents. We noted durable and sustained improvements in glycemia which persist long after treatment withdrawal. Ab-4 promoted ß-cell survival and enhanced the recovery of insulin+ islet mass with concomitant increases in circulating insulin and C peptide. In PANIC-ATTAC mice, an inducible model of ß-cell apoptosis which allows for robust assessment of ß-cell regeneration following caspase-8-induced diabetes, Ab-4 drove a 6.7-fold increase in ß-cell mass. Lineage tracing suggests that this restoration of functional insulin-producing cells was at least partially driven by α-cell-to-ß-cell conversion. Following hyperglycemic onset in nonobese diabetic (NOD) mice, Ab-4 treatment promoted improvements in C-peptide levels and insulin+ islet mass was dramatically increased. Lastly, diabetic mice receiving human islet xenografts showed stable improvements in glycemic control and increased human insulin secretion.

Two-Pronged Microbe Delivery of Nitric Oxide and Oxygen for Diabetic Wound Healing.

Chronic inflammation and hypoxia in the microenvironment of diabetic foot ulcers (DFUs) can result in sustained vascular impairment, hindering tissue regeneration. While both nitric oxide and oxygen have been shown to promote wound healing in DFUs through anti-inflammatory and neovascularization, there is currently no available therapy that delivers both. We present a novel hydrogel consisting of Weissella and Chlorella, which alternates between nitric oxide and oxygen production to reduce chronic inflammation and hypoxia. Further experiments indicate that the hydrogel accelerates wound closure, re-epithelialization, and angiogenesis in diabetic mice and improves the survival of skin grafts. This dual-gas therapy holds promise as a potential treatment option for the management of diabetic wounds.