Elucidation of DPP-4 involvement in systemic distribution and renal reabsorption of linagliptin by PBPK modeling with a cluster Gauss-Newton method.

The dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin (LNG) exhibits target-mediated drug disposition (TMDD) in clinical settings, characterized by saturable binding to plasma soluble DPP-4 (sDPP-4) and tissue transmembrane DPP-4 (tDPP-4). Previous studies have indicated that saturable renal reabsorption of LNG contributes to its nonlinear urinary excretion observed in humans and wild-type mice, but not in Dpp-4 knockout mice. To elucidate the mechanisms underlying these complex phenomena, including DPP-4-related renal reabsorption of LNG, we employed physiologically-based pharmacokinetic (PBPK) modeling combined with a cluster Gauss-Newton method (CGNM). The CGNM facilitated the exploration of parameters in rat and human PBPK models for LNG and the determination of parameter identifiability. Through PBPK-CGNM analysis using reported autoradiography data ([14C]-LNG) in wild-type and Dpp-4-deficient rats, DPP-4-specific distributions of LNG in various tissues were clearly differentiated from nonspecific parts. By fitting to human plasma concentrations and urinary and fecal excretions of LNG after intravenous and oral administrations, multiple unknown PBPK parameters were simultaneously estimated by the CGNM. Notably, the amount of tDPP-4 and the reabsorption clearance for LNG-DPP-4 complexes were identifiable, indicating their critical role in explaining the complex nonlinear pharmacokinetics of LNG. Compared with previous PBPK analyses, the CGNM allowed us to incorporate greater model complexity (e.g., consideration of tDPP-4 expressions and in vitro binding kinetics), ultimately resulting in a more accurate reproduction of LNG's TMDD. In conclusion, by considering LNG as a high-affinity probe for DPP-4, comprehensive PBPK-CGNM analyses suggested a dynamic whole-body distribution of DPP-4, including its involvement in the renal reabsorption of LNG.

Intense simplified strategy for newly diagnosed type 2 diabetes in patients with severe hyperglycaemia: multicentre, open label, randomised trial.

OBJECTIVE: To evaluate whether the intense simplified strategy, which comprises short term intensive insulin therapy (SIIT) followed by subsequent oral antihyperglycaemic regimens, could improve long term glycaemic outcomes in patients with newly diagnosed type 2 diabetes mellitus and severe hyperglycaemia. DESIGN: Multicentre, open label, randomised trial. SETTING: 15 hospitals in China between December 2017 and December 2020. PARTICIPANTS: 412 patients with newly diagnosed type 2 diabetes and significant hyperglycaemia (HbA1c ≥8.5%). INTERVENTIONS: All randomised participants initially received SIIT for 2-3 weeks, followed by linagliptin 5 mg/day, metformin 1000 mg/day, combination linagliptin plus metformin, or lifestyle modification alone (control) for 48 weeks. MAIN OUTCOME MEASURES: The primary outcome was the percentage of participants achieving HbA1c <7.0% at week 48 after SIIT. Secondary outcomes included glycaemic control, ß cell function, and variations in insulin sensitivity. RESULTS: 412 participants were randomised. At baseline, the mean age was 46.8 (standard deviation 11.2) years, mean body mass index was 25.8 (2.9), and mean HbA1c was 11.0% (1.9%). At week 48, 80% (78/97), 72% (63/88), and 73% (69/95) of patients in the linagliptin plus metformin, linagliptin, and metformin groups, respectively, achieved HbA1c <7.0%, compared with 60% (56/93) in the control group (P=0.02 overall; P=0.003 for linagliptin plus metformin versus control; P=0.12 for linagliptin versus control; P=0.09 for metformin versus control). Additionally, 70% (68/97), 68% (60/88), and 68% (65/95) of patients in the linagliptin plus metformin, linagliptin, and metformin group, respectively, achieved HbA1c <6.5% compared with 48% (45/93) in the control group (P=0.005 overall; P=0.005 for linagliptin plus metformin versus control; P=0.01 for linagliptin versus control; P=0.008 for metformin versus control; all were significant after adjustment for multiple comparisons). Thus, compared with the control group, participants in the linagliptin plus metformin group were more likely to achieve HbA1c <7.0% at week 48 (odds ratio 2.78, 95% confidence interval 1.37 to 5.65; P=0.005). Moreover, the linagliptin plus metformin group showed the most significant improvement in fasting plasma glucose and ß cell function indices. All treatments were well tolerated. CONCLUSIONS: The intense simplified strategy using subsequent oral therapies post-SIIT, especially the linagliptin plus metformin combination, sustainably improved glycaemic control and ß cell function in patients with newly diagnosed type 2 diabetes mellitus and severe hyperglycaemia. This approach offers a promising direction for decision making in the clinical management of type 2 diabetes mellitus. TRIAL REGISTRATION: ClinicalTrials.gov NCT03194945.

Antiproliferative Impact of Linagliptin on the Cervical Cancer Cell Line.

OBJECTIVE: This study aimed to assess linagliptin's inhibitory effects on the proliferation of cervical cancer cell lines and investigate its potential for targeting human heat shock protein 90. METHODS: Linagliptin's cytotoxicity was assessed on a cervical cancer cell line (Hela cancer cell line) at two different incubation periods, 24 and 72 hours. The molecular docking between linagliptin and the receptor protein human Hsp 90 (PDB code: 5XRE) was performed using the Biovia Discovery Studio and AutoDock tool software. The Discovery Studio visualizer generated three-dimensional (3D) and two-dimensional (2D) interactive images. RESULTS: The study's cytotoxicity results demonstrated that linagliptin can inhibit the proliferation of cervical cancer cells. The cytotoxicity exhibited a time-dependent pattern (cell cycle specific). The molecular docking study was conducted to investigate the interaction between linagliptin and human Hsp90. The study identified 11 sites where linagliptin can bind to Hsp90 amino acid residues. The total docking score for this interaction was -10.3 kcal/mol. The most potent binding occurred through conventional hydrogen bonds with the ASP:54 amino acid residues at a distance of 2.93 Å. The docking scores for linagliptin were comparable to those of the reference drug geldanamycin, indicating a strong interaction between linagliptin and Hsp90. CONCLUSION: The study has found that linagliptin successfully reduces the growth of cervical cancer cells with a time-dependent cytotoxic pattern. The potential anticancer mechanism of linagliptin can be inferred by analyzing the docking score and docking pattern between linagliptin and Hsp90, suggesting that linagliptin targets human Hsp 90.

Sustained linagliptin administration: superior glycemic control and less pancreatic injury in diabetic rats.

While linagliptin is the most potent dipeptidyl peptidase 4 inhibitor, its use is limited due to poor bioavailability and the potential risk of pancreatic injury. Here, we investigated whether the sustained weekly administration of linagliptin could provide better effect compared to frequent daily oral administration. Type 2 diabetes was induced by feeding rats a high fructose/fat/salt diet followed by STZ injection. Compared to the partial glycemic control achieved with daily oral linagliptin, a weekly subcutaneous injection containing about one-fourth of the oral dose produced superior glycemic control, as evidenced by the 4-week postprandial glucose follow-up and oral glucose tolerance test. This was confirmed by the significant increase in serum insulin in the case of the sustained linagliptin administration. Higher levels of the anti-inflammatory cytokine adiponectin and lower triglyceride levels were observed after sustained linagliptin administration compared with daily oral linagliptin. In addition, sustained linagliptin displayed a significant increase in ß-cells' insulin immunoreactivity when compared with daily linagliptin. More reduction in collagen deposition and caspase-3 immunoreactivity in pancreatic tissue were observed in sustained linagliptin compared with oral linagliptin. In conclusion, sustained linagliptin administration provided superior glycemic control, which seems to be mediated by more reduction in pancreatic injury.

Cofrogliptin once every 2 weeks as add-on therapy to metformin versus daily linagliptin in patients with type 2 diabetes in China: A randomized, double-blind, non-inferiority trial.

AIM: We evaluated the efficacy and safety of cofrogliptin, a novel dipeptidyl peptidase-4 inhibitor taken once every 2 weeks (Q2W), compared with linagliptin (taken daily) in patients with type 2 diabetes inadequately controlled on metformin in China. MATERIALS AND METHODS: In this phase 3 randomized, double-blind, active-controlled, multicentre study, patients were randomly assigned 1:1:1 to receive cofrogliptin 10 mg Q2W, cofrogliptin 25 mg Q2W, or linagliptin 5 mg daily, all as an add-on treatment to metformin, for 24 weeks. Eligible patients could enter an open-label extension period and receive cofrogliptin 25 mg Q2W for an additional 28 weeks. The primary endpoint was change in glycated haemoglobin from baseline to 24 weeks, with a non-inferiority margin of 0.4% for cofrogliptin versus linagliptin treatment. RESULTS: Overall, 465 patients entered the 24-week treatment period (median age: 57.0 years). The least-squares mean (standard error) change in glycated haemoglobin from baseline to week 24 was -0.96 (0.063), -0.99 (0.064) and -1.07 (0.065) for the cofrogliptin 10 mg, cofrogliptin 25 mg and linagliptin 5 mg groups, respectively. The between-group difference met the predefined margin for non-inferiority of cofrogliptin (10 and 25 mg) versus linagliptin treatment. The incidence of common adverse events (≥5% patients) during the 24-week treatment period was similar between treatment groups. There were no serious hypoglycaemic events. CONCLUSION: In Chinese patients with type 2 diabetes inadequately controlled on metformin, the glucose-lowering effect of cofrogliptin (Q2W) was non-inferior to linagliptin (daily), with a similar safety profile maintained over 52 weeks of treatment.

Linagliptin mitigates cisplatin-induced kidney impairment via mitophagy regulation in rats, with emphasis on SIRT-3/PGC-1α, PINK-1 and Parkin-2.

Cisplatin (CDDP) often leads to kidney impairment, limiting its effectiveness in cancer treatment. The lack of mitophagy in proximal tubules exacerbates this issue. Hence, targeting SIRT-3 and PGC1-α shows promise in mitigating CDDP-induced kidney damage. The potential renoprotective effects of linagliptin, however, remain poorly understood. This study represents the first exploration of linagliptin's impact on CDDP-induced kidney impairment in rats, emphasizing its potential role in mitophagic pathways. The experiment involved four rat groups: Group (I) received saline only, Group (II) received a single intraperitoneal injection of CDDP at 6 mg/kg. Groups (III) and (IV) received linagliptin at 6 and 10 mg/kg p.o., respectively, seven days before CDDP administration, continuing for an additional four days. Various parameters, including renal function tests, oxidative stress, TNF-α, IL-1ß, IL-6, PGC-1α, FOXO-3a, p-ERK1, and the gene expression of SIRT-3 and P62 in renal tissue, were assessed. Linagliptin improved renal function, increased antioxidant enzyme activity, and decreased IL-1ß, TNF-α, and IL-6 expression. Additionally, linagliptin significantly upregulated PGC-1α and PINK-1/Parkin-2 expression while downregulating P62 expression. Moreover, linagliptin activated FOXO-3a and SIRT-3, suggesting a potential enhancement of mitophagy. Linagliptin demonstrated a positive impact on various factors related to kidney health in the context of CDDP-induced impairment. These findings suggest a potential role for linagliptin in improving cancer treatment outcomes. Clinical trials are warranted to further investigate and validate its efficacy in a clinical setting.

Machine learning assessment of vildagliptin and linagliptin effectiveness in type 2 diabetes: Predictors of glycemic control.

OBJECTIVE: Differential effects of linagliptin and vildagliptin may help us personalize treatment for Type 2 Diabetes Mellitus (T2DM). The current study compares the effect of these drugs on glycated hemoglobin (HbA1c) in an artificial neural network (ANN) model. METHODS: Patients with T2DM who received either vildagliptin or linagliptin, with predefined exclusion criteria, qualified for the study. Two input variable datasets were constructed: with or without imputation for missing values. The primary outcome was HbA1c readings between 3 to 12 months or the reduction in HbA1c levels. RESULTS: The cohort comprised 191 individuals (92 vildagliptin and 99 linagliptin). Linagliptin group had significantly higher disease burden. For imputed dataset, HbA1c was lower with linagliptin at 3 to 12 months (7.442 ± 0.408 vs. 7.626 ± 0.408, P < 0.001). However, there was a small yet significant difference in HbA1c reduction favoring vildagliptin over linagliptin (-1.123 ± 0.033 vs. -1.111 ± 0.043, P < 0.001). LDL level, uric acid, and the drug group were identified as predictors for HbA1c levels. In the non-imputed dataset HbA1c at 3 to 12 months was lower with linagliptin (median ± IQR: 7.489 ± 0.467 vs. 7.634 ± 0.467, P-value < 0.001). However, both linagliptin and vildagliptin exhibited similar reductions in HbA1c levels (both median ± IQR of -1.07 ± 0.02). Predictors for HbA1c levels included eGFR level and the drug group. CONCLUSION: Linagliptin effectively lowers HbA1c levels more than vildagliptin including in patients with comorbidities. DPP4-I choice is a constant predictor of HbA1c in all models.

Dipeptidyl Peptidase (DPP)-4 Inhibitors and Pituitary Adenylate Cyclase-Activating Polypeptide, a DPP-4 Substrate, Extend Neurite Outgrowth of Mouse Dorsal Root Ganglia Neurons: A Promising Approach in Diabetic Polyneuropathy Treatment.

Individuals suffering from diabetic polyneuropathy (DPN) experience debilitating symptoms such as pain, paranesthesia, and sensory disturbances, prompting a quest for effective treatments. Dipeptidyl-peptidase (DPP)-4 inhibitors, recognized for their potential in ameliorating DPN, have sparked interest, yet the precise mechanism underlying their neurotrophic impact on the peripheral nerve system (PNS) remains elusive. Our study delves into the neurotrophic effects of DPP-4 inhibitors, including Diprotin A, linagliptin, and sitagliptin, alongside pituitary adenylate cyclase-activating polypeptide (PACAP), Neuropeptide Y (NPY), and Stromal cell-derived factor (SDF)-1a-known DPP-4 substrates with neurotrophic properties. Utilizing primary culture dorsal root ganglia (DRG) neurons, we meticulously evaluated neurite outgrowth in response to these agents. Remarkably, all DPP-4 inhibitors and PACAP demonstrated a significant elongation of neurite length in DRG neurons (PACAP 0.1 µM: 2221 ± 466 µm, control: 1379 ± 420, p < 0.0001), underscoring their potential in nerve regeneration. Conversely, NPY and SDF-1a failed to induce neurite elongation, accentuating the unique neurotrophic properties of DPP-4 inhibition and PACAP. Our findings suggest that the upregulation of PACAP, facilitated by DPP-4 inhibition, plays a pivotal role in promoting neurite elongation within the PNS, presenting a promising avenue for the development of novel DPN therapies with enhanced neurodegenerative capabilities.

Macrophages communicate with mesangial cells through the CXCL12/DPP4 axis in lupus nephritis pathogenesis.

Lupus nephritis (LN) occurs in 50% of cases of systemic lupus erythematosus (SLE) and is one of the most serious complications that can occur during lupus progression. Mesangial cells (MCs) are intrinsic cells in the kidney that can regulate capillary blood flow, phagocytose apoptotic cells, and secrete vasoactive substances and growth factors. Previous studies have shown that various types of inflammatory cells can activate MCs for hyperproliferation, leading to disruption of the filtration barrier and impairment of renal function in LN. Here, we characterized the heterogeneity of kidney cells of LN mice by single-nucleus RNA sequencing (snRNA-seq) and revealed the interaction between macrophages and MCs through the CXC motif chemokine ligand 12 (CXCL12)/dipeptidyl peptidase 4 (DPP4) axis. In culture, macrophages modulated the proliferation and migration of MCs through this ligand-receptor interaction. In LN mice, treatment with linagliptin, a DPP4 inhibitor, effectively inhibited MC proliferation and reduced urinary protein levels. Together, our findings indicated that targeting the CXCL12/DPP4 axis with linagliptin treatment may serve as a novel strategy for the treatment of LN via the CXCL12/DPP4 axis.

Linagliptin Mitigates TGF-ß1 Mediated Epithelial-Mesenchymal Transition in Tacrolimus-Induced Renal Interstitial Fibrosis via Smad/ERK/P38 and HIF-1α/LOXL2 Signaling Pathways.

The dipeptidyl peptidase-4 (DPP-4) inhibitors, a novel anti-diabetic medication family, are renoprotective in diabetes, but a comparable benefit in chronic non-diabetic kidney diseases is still under investigation. This study aimed to elucidate the molecular mechanisms of linagliptin's (Lina) protective role in a rat model of chronic kidney injury caused by tacrolimus (TAC) independent of blood glucose levels. Thirty-two adult male Sprague Dawley rats were equally randomized into four groups and treated daily for 28 d as follows: The control group; received olive oil (1 mL/kg/d, subcutaneously), group 2; received Lina (5 mg/kg/d, orally), group 3; received TAC (1.5 mg/kg/d, subcutaneously), group 4; received TAC plus Lina concomitantly in doses as the same previous groups. Blood and urine samples were collected to investigate renal function indices and tubular injury markers. Additionally, signaling molecules, epithelial-mesenchymal transition (EMT), and fibrotic-related proteins in kidney tissue were assessed by enzyme-linked immunosorbent assay (ELISA) and Western blot analysis, immunohistochemical and histological examinations. Tacrolimus markedly induced renal injury and fibrosis as indicated by renal dysfunction, histological damage, and deposition of extracellular matrix (ECM) proteins. It also increased transforming growth factor ß1 (TGF-ß1), Smad4, p-extracellular signal-regulated kinase (ERK)1/2/ERK1/2, and p-P38/P38 mitogen-activated protein kinase (MAPK) protein levels. These alterations were markedly attenuated by the Lina administration. Moreover, Lina significantly inhibited EMT, evidenced by inhibiting Vimentin and α-smooth muscle actin (α-SMA) and elevating E-cadherin. Furthermore, Lina diminished hypoxia-related protein levels with a subsequent reduction in Snail and Twist expressions. We concluded that Lina may protect against TAC-induced interstitial fibrosis by modulating TGF-ß1 mediated EMT via Smad-dependent and independent signaling pathways.

Linagliptin ameliorates tacrolimus-induced renal injury: role of Nrf2/HO-1 and HIF-1α/CTGF/PAI-1.

BACKGROUND: Tacrolimus (TAC) is a frequently used immunosuppressive medication in organ transplantation. However, its nephrotoxic impact limits its long-term usage. This study aims to investigate the effect of linagliptin (Lina) on TAC-induced renal injury and its underlying mechanisms. METHODS AND RESULTS: Thirty-two Sprague Dawley rats were treated with TAC (1.5 mg/kg/day, subcutaneously) and/or Lina (5 mg/kg/day, orally) for 4 weeks. Histological examination was conducted, and serum and urinary biomarkers were measured to assess kidney function and integrity. Furthermore, ELISA, Western blot analysis and immunohistochemical assay were employed to determine signaling molecules of oxidative stress, profibrogenic, hypoxic, and apoptotic proteins. Tacrolimus caused renal dysfunction and histological deterioration evidenced by increased serum creatinine, blood urea nitrogen (BUN), urinary cystatin C, and decreased serum albumin as well as elevated tubular injury and interstitial fibrosis scores. Additionally, TAC significantly increased the expression of collagen type-1, alpha-smooth muscle actin (α-SMA), plasminogen activator inhibitor-1 (PAI-1), and transforming growth factor-beta1 (TGF-ß1) renal content. Moreover, TAC decreased the expression of nuclear factor erythroid-2-related factor2 (Nrf2), heme oxygenase 1 (HO-1), and mitochondrial superoxide dismutase (SOD2). In addition, TAC increased protein expression of hypoxia-inducible factor1-alpha (HIF-1α), connective tissue growth factor (CTGF), inducible nitric oxide synthase (iNOS), 8-hydroxy-2-deoxyguanosine (8-OHdG), as well as nitric oxide (NO), 4-hydroxynonenal, caspase-3 and Bax renal contents. Furthermore, TAC decreased Bcl-2 renal contents. The Lina administration markedly attenuated these alterations. CONCLUSION: Lina ameliorated TAC-induced kidney injury through modulation of oxidative stress, hypoxia, and apoptosis related proteins.

Is GFR decline induced by SGLT2 inhibitor of clinical importance?

BACKGROUND: Use of sodium-glucose-cotransporter-2 (SGLT2) inhibitors often causes an initial decline in glomerular filtration rate (GFR). This study addresses the question whether the initial decline of renal function with SGLT2 inhibitor treatment is related to vascular changes in the systemic circulation. METHODS: We measured GFR (mGFR) and estimated GFR (eGFR) in 65 patients with type 2 diabetes (T2D) at baseline and after 12 weeks of treatment randomized either to a combination of empagliflozin and linagliptin (SGLT2 inhibitor based treatment group) (n = 34) or metformin and insulin (non-SGLT2 inhibitor based treatment group) (n = 31). mGFR was measured using the gold standard clearance technique by constant infusion of inulin. In addition to blood pressure (BP), we measured pulse wave velocity (PWV) under standardized conditions reflecting vascular compliance of large arteries, as PWV is considered to be one of the most reliable vascular parameter of cardiovascular (CV) prognosis. RESULTS: Both mGFR and eGFR decreased significantly after initiating treatment, but no correlation was found between change in mGFR and change in eGFR in either treatment group (SGLT2 inhibitor based treatment group: r=-0.148, p = 0.404; non-SGLT2 inhibitor based treatment group: r = 0.138, p = 0.460). Noticeably, change in mGFR correlated with change in PWV (r = 0.476, p = 0.005) in the SGLT2 inhibitor based treatment group only and remained significant after adjustment for the change in systolic BP and the change in heart rate (r = 0.422, p = 0.018). No such correlation was observed between the change in eGFR and the change in PWV in either treatment group. CONCLUSIONS: Our main finding is that after initiating a SGLT2 inhibitor based therapy an exaggerated decline in mGFR was related with improved vascular compliance of large arteries reflecting the pharmacologic effects of SGLT2 inhibitor in the renal and systemic vascular bed. Second, in a single patient with T2D, eGFR may not be an appropriate parameter to assess the true change of renal function after receiving SGLT2 inhibitor based therapy. TRIAL REGISTRATION: clinicaltrials.gov (NCT02752113).

Unveiling Pharmacokinetics and Drug Interaction of Linagliptin and Pioglitazone HCl in Rat Plasma Using LC-MS/MS.

The linagliptin (LIN) and pioglitazone HCl (PIO) combination, currently undergoing phase III clinical trials for diabetes mellitus treatment, demonstrated significant improvements in glycemic control. However, the absence of an analytical method for simultaneous determination in biological fluids highlights a crucial gap. This underscores the pressing need for sensitive bioanalytical methods, emphasizing the paramount importance of developing such tools to advance diabetes management strategies and enhance patient care. Herein, a sensitive reverse-phase high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry method was developed for simultaneous determination of LIN and PIO in rat plasma using alogliptin as an internal standard. Chromatographic separation was performed on an Agilent Eclipse Plus C18 (4.6 × 100 mm, 3.5 µm) using an isocratic mobile phase system consisting of ammonium formate (pH 4.5) and methanol using an acetonitrile-induced protein precipitation technique for sample preparation. Multiple reaction monitoring in positive ion mode was used for quantitation of the precursor to production at m/z 473.2 → 419.9 for LIN, 357.1 → 134.2 for PIO, and 340.3 → 116.1 for ALO. The linearity range was 0.5 to 100 and 1 to 2000 ng/mL for LIN and PIO, respectively. The developed method was validated as per US-FDA guidelines and successfully applied to clinical pharmacokinetic and drug-drug interaction studies with a single oral administration of LIN and PIO in rat plasma. Pharmacokinetic parameters of LIN were significantly influenced by the concomitant administration of PIO and vice versa. Molecular modeling revealed the significant interaction of LIN and PIO with P-glycoprotein. Therefore, the drug-drug interaction between LIN and PIO deserves further study to improve drug therapy and prevent dangerous adverse effects.

Effect of metformin and metformin/linagliptin on gut microbiota in patients with prediabetes.

Lifestyle modifications, metformin, and linagliptin reduce the incidence of type 2 diabetes (T2D) in people with prediabetes. The gut microbiota (GM) may enhance such interventions' efficacy. We determined the effect of linagliptin/metformin (LM) vs metformin (M) on GM composition and its relationship to insulin sensitivity (IS) and pancreatic ß-cell function (Pßf) in patients with prediabetes. A cross-sectional study was conducted at different times: basal, six, and twelve months in 167 Mexican adults with prediabetes. These treatments increased the abundance of GM SCFA-producing bacteria M (Fusicatenibacter and Blautia) and LM (Roseburia, Bifidobacterium, and [Eubacterium] hallii group). We performed a mediation analysis with structural equation models (SEM). In conclusion, M and LM therapies improve insulin sensitivity and Pßf in prediabetics. GM is partially associated with these improvements since the SEM models suggest a weak association between specific bacterial genera and improvements in IS and Pßf.

Linagliptin decreased the tumor progression on glioblastoma model.

PURPOSE: Dipeptidyl peptidase-4 (DPP-4) inhibitors are oral hypoglycemic drugs and are used for type II diabetes. Previous studies showed that DPP-4 expression is observed in several tumor types and DPP-4 inhibitors suppress the tumor progression on murine tumor models. In this study, we evaluated the role of DPP-4 and the antitumor effect of a DPP-4 inhibitor, linagliptin, on glioblastoma (GBM). METHODS: We analyzed DPP-4 expression in glioma patients by the public database. We also analyzed DPP-4 expression in GBM cells and the murine GBM model. Then, we evaluated the cell viability, cell proliferation, cell migration, and expression of some proteins on GBM cells with linagliptin. Furthermore, we evaluated the antitumor effect of linagliptin in the murine GBM model. RESULTS: The upregulation of DPP-4 expression were observed in human GBM tissue and murine GBM model. In addition, DPP-4 expression levels were found to positively correlate with the grade of glioma patients. Linagliptin suppressed cell viability, cell proliferation, and cell migration in GBM cells. Linagliptin changed the expression of phosphorylated NF-kB, cell cycle, and cell adhesion-related proteins. Furthermore, oral administration of linagliptin decreases the tumor progression in the murine GBM model. CONCLUSION: Inhibition of DPP-4 by linagliptin showed the antitumor effect on GBM cells and the murine GBM model. The antitumor effects of linagliptin is suggested to be based on the changes in the expression of several proteins related to cell cycle and cell adhesion via the regulation of phosphorylated NF-kB. This study suggested that DPP-4 inhibitors could be a new therapeutic strategy for GBM.

Safety of Linagliptin in Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis of Randomized Clinical Trials.

BACKGROUND: Linagliptin is an oral dipeptidyl peptidase DPP-4 inhibitor, which is indicated for the treatment of Type 2 diabetes mellitus (T2DM) as monotherapy or add-on to therapy with other hypoglycemic drugs. OBJECTIVES: We aimed to summarize the evidence from randomized controlled trials (RCTs) to assess the safety of linagliptin focusing on cardiovascular risks among subjects with type 2 diabetes mellitus. METHODS: We conducted a systematic search across the following databases: Medline, Embase, the Cochrane Central Register of Controlled Trials and ClinicalTrials.gov from inception to November 2021. Randomized controlled trials (RCTs) of linagliptin compared to placebo in patients with Type 2 diabetes were included. The primary safety points were cardiovascular (CV) adverse events including non-fatal stroke, non-fatal myocardial infarction (MI), CV death, MI, stroke, and hospitalization for unstable angina. While, secondary safety points included 17 reported adverse events such as infections, hypoglycemia and abdominal pain. Three reviewers independently screened and reviewed each study to extract relevant information. Any discrepancies were resolved by consensus. We conducted a meta-analysis using the random effects model. Pooled risk ratios (RRs) of targeted adverse events with linagliptin compared to placebo were estimated using the Mantel-Haenszel test. RESULTS: A total of 24 studies with 19,981 adult patients were included. There was no difference in the incidence of all CV adverse events or individual CV adverse events between linagliptin and the placebo arms. The pooled estimate of the risk of upper respiratory tract infection was reported in twelve trials with a 38% risk reduction among patients treated with the linagliptin group compared to the placebo group (RR = 0.62, 95% CI: 0.45-0.85, and I2 = 0%), while no difference was found in other infections. For gastrointestinal disorders, the risk of abdominal pain showed a 65% risk reduction among patients treated with the linagliptin group compared to the placebo group (RR = 0.35, 95% CI: 0.16-0.77, and I2 = 0%). CONCLUSION: Our study showed an overall acceptable safety profile of linagliptin in patients with T2DM. Moreover, our study showed a risk reduction of upper respiratory tract infection and abdominal pain when using linagliptin compared to placebo.

Identification of Risk Factors for Gliptin-associated Bullous Pemphigoid among Diabetic Patients.

Drug-associated bullous pemphigoid has been shown to follow long-term gliptin (dipeptidyl-peptidase 4 inhibitors) intake. This study aimed at identifying risk factors for gliptin-associated bullous pemphigoid among patients with type 2 diabetes. A retrospective study was conducted in a tertiary centre among diabetic patients exposed to gliptins between the years 2008-2021. Data including demographics, comorbidities, medications, and laboratory results were collected using the MDClone platform. Seventy-six patients with type 2 diabetes treated with dipeptidyl-peptidase 4 inhibitors who subsequently developed bullous pemphigoid were compared with a cohort of 8,060 diabetic patients exposed to dipeptidyl-peptidase 4 inhibitors who did not develop bullous pemphigoid. Based on a multivariable analysis adjusted for age and other covariates, Alzheimer's disease and other dementias were significantly more prevalent in patients with bullous pemphigoid (p = 0.0013). Concomitant use of either thiazide or loop diuretics and gliptin therapy was associated with drug-associated bullous pemphigoid (p < 0.0001 for both). While compared with sitagliptin, exposure to linagliptin and vildagliptin were associated with bullous pemphigoid with an odds ratio of 5.68 and 6.61 (p < 0.0001 for both), respectively. These results suggest gliptins should be prescribed with caution to patients with type 2 diabetes with coexisting Alzheimer's and other dementias, or patients receiving long-term use of thiazides and loop diuretics. The use of sitagliptin over linagliptin and vildagliptin should be preferred in these patients.