The neurovascular protective effect of alogliptin in murine MCAO model and brain endothelial cells

Fenofibrate maintains the integrity of the blood-brain barrier during cerebral ischemia-reperfusion injury by inhibiting Egr- 1

Blood-brain barrier (BBB) damage and dysfunction are critical pathological features associated with cerebral ischemia-reperfusion injury in stroke. Fenofibrate, a lipid-regulating drug, has an unclear role in BBB function during stroke. This study investigates the effects of fenofibrate on BBB disruption and cerebrovascular endothelial cells induced by ischemia-reperfusion. Cerebral ischemia-reperfusion injury (CIRI) models were established using the middle cerebral artery occlusion (MCAO) method. Blood-brain barrier (BBB) integrity was assessed using Evans blue dye. The permeability of human brain microvascular endothelial cells (HBMVECs) was evaluated using fluorescein isothiocyanate (FITC)-dextran permeation assays and trans-endothelial electrical resistance (TEER) measurements. Additionally, real-time polymerase chain reaction (PCR), immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis were performed. We found that the administration of fenofibrate improved brain endothelial dysfunction by reducing the expression of vascular cell adhesion molecule- 1 (VCAM- 1) and E-selectin in MCAO mice. Furthermore, fenofibrate restored the expression of the tight junction protein occludin in the cortices of MCAO mice. Notably, fenofibrate alleviated BBB dysfunction in MCAO mice. In vitro studies demonstrated that fenofibrate ameliorated endothelial monolayer permeability under oxygen-glucose deprivation/reoxygenation (OGD/R) conditions and inhibited the expression of VCAM- 1 and E-selectin in HBMVECs. Moreover, fenofibrate restored occludin expression following OGD/R. We identified a novel mechanism whereby fenofibrate suppressed the elevation of Egr- 1 induced by OGD/R; however, overexpression of Egr- 1 abrogated the protective effects of fenofibrate on the upregulation of VCAM- 1 and E-selectin and the downregulation of occludin induced by OGD/R. Furthermore, overexpression of early growth response- 1 (Egr- 1) negated the protective effects of fenofibrate on endothelial monolayer permeability and trans-endothelial electrical resistance (TEER). Our findings suggest that fenofibrate may be a promising therapeutic agent for stroke treatment.

Exploring DPP IV inhibitors for Alzheimer's disease: Bridging diabetes and neurodegeneration

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by neurofibrillary tangles (NFTs), senile plaques from Aβ deposits, neuronal inflammation, oxidative stress, and impaired neuronal transmission involving acetylcholine and glutamate. Diabetes patients are at a higher risk of developing AD-like pathology due to shared pathological and molecular mechanisms, including insulin resistance, oxidative stress, formation of advanced glycation end products (AGEs), and overactive immune systems. Current treatments of AD typically address only one aspect of the disease, rather than treating it as a multifactorial process. Targeting cerebral glucose-insulin metabolism has emerged as a promising strategy for AD management. Numerous studies show positive correlations between anti-diabetic drugs and AD management. Among these, DPP IV inhibitors have demonstrated significant therapeutic benefits against AD in experimental settings. DPP IV inhibitors have been shown to significantly reduce Aβ oligomerization, phosphorylated tau (p-tau), oxidative stress, and inflammatory markers, presenting a potentially effective approach for targeting AD-like pathology. Although preclinical data are promising, clinical trials are needed to validate these findings and establish the safety and efficacy of DPP IV inhibitors as a therapeutic intervention for AD. This could represent a novel approach for addressing both the metabolic and neurodegenerative aspects of AD.

Post-acute ischemic stroke hyperglycemia aggravates destruction of the blood-brain barrier

Post-acute ischemic stroke hyperglycemia increases the risk of hemorrhagic transformation, which is associated with blood-brain barrier disruption. Brain microvascular endothelial cells are a major component of the blood-brain barrier. Intercellular mitochondrial transfer has emerged as a novel paradigm for repairing cells with mitochondrial dysfunction. In this study, we first investigated whether mitochondrial transfer exists between brain microvascular endothelial cells, and then investigated the effects of post-acute ischemic stroke hyperglycemia on mitochondrial transfer between brain microvascular endothelial cells. We found that healthy brain microvascular endothelial cells can transfer intact mitochondria to oxygen glucose deprivation-injured brain microvascular endothelial cells. However, post-oxygen glucose deprivation hyperglycemia hindered mitochondrial transfer and exacerbated mitochondrial dysfunction. We established an in vitro brain microvascular endothelial cell model of the blood-brain barrier. We found that post-acute ischemic stroke hyperglycemia reduced the overall energy metabolism levels of brain microvascular endothelial cells and increased permeability of the blood-brain barrier. In a clinical study, we retrospectively analyzed the relationship between post-acute ischemic stroke hyperglycemia and the severity of hemorrhagic transformation. We found that post-acute ischemic stroke hyperglycemia serves as an independent predictor of severe hemorrhagic transformation. These findings suggest that post-acute ischemic stroke hyperglycemia can aggravate disruption of the blood-brain barrier by inhibiting mitochondrial transfer.

Small molecule compound K-7174 attenuates neuropsychiatric manifestations in lupus-prone mice

The neuropsychiatric manifestations of systemic lupus erythematosus (NPSLE) present significant morbidity and mortality due to frequent non-response or adverse effects of the current clinical drugs. The disruption of the blood-brain barrier (BBB) contributes to inflammatory NPSLE disease progression. K-7174, a highly piperazine-derived compound, inhibits leukocyte adhesion and inflammatory factor expression. The present study aimed to comprehensively assess the treatment effect of neurobehavioral deficits in MRL/lpr mice, a validated neuropsychiatric lupus model. The intraperitoneal injection of K-7174 alleviated lupus-like symptoms and improved cognitive dysfunction in MRL/lpr mice. Also, it significantly attenuated neuronal degeneration and decreased serum albumin deposition in the hippocampus. Furthermore, K-7174 acted directly on the brain microvascular endothelial bEnd.3 cells and reduced the BBB permeability, manifested by inhibiting the activation of brain microvascular endothelial cells and increasing the expression of tight junctions (TJs). Notably, in vitro experiments showed that K-7174 alleviates the decreased ZO1 and Occludin expression in bEnd.3 cells caused by lactate increase, improving cell permeability via the MCT4/NKAP/CREB signaling pathway. These findings suggested that K-7174 mediates the attenuation of NPSLE in MRL/lpr mice, indicating a promising therapeutic strategy for NPSLE.

Dipeptidyl peptidase 4(DPP4) inhibitors stride up the management of Parkinson's disease

Parkinson's disease (PD) is the 2^nd most common age-related hypokinetic disorder, characterized by dopaminergic degeneration and movement abnormalities. Dopaminergic degeneration in the basal ganglia is primarily seen in PD patients. The therapeutic strategies currently under investigation are to rescue dopaminergic degeneration and promote neuronal regeneration, which could halt disease progression. On the other hand, the therapeutic efficacy of existing drugs used in other disorders has been repurposed in neurodegenerative pathologies. DPP4 inhibitors widely used in treating diabetes have been considered viable target sites and are being tested for efficacy in neurodegenerative pathologies. DPP4 inhibitors have been reported to rescue neuronal degeneration and improve motor functions in various preclinical and clinical PD studies. The current review is focused on the neuroprotective potential, molecular mechanisms and therapeutic potential of DPP4 inhibitors in PD pathology.

Factors influencing the blood-brain barrier permeability

The blood-brain barrier (BBB) is a dynamic structure that protects the brain from harmful blood-borne, endogenous and exogenous substances and maintains the homeostatic microenvironment. All constituent cell types play indispensable roles in the BBB's integrity, and other structural BBB components, such as tight junction proteins, adherens junctions, and junctional proteins, can control the barrier permeability. Regarding the need to exchange nutrients and toxic materials, solute carriers, ATP-binding case families, and ion transporter, as well as transcytosis regulate the influx and efflux transport, while the difference in localisation and expression can contribute to functional differences in transport properties. Numerous chemical mediators and other factors such as non-physicochemical factors have been identified to alter BBB permeability by mediating the structural components and barrier function, because of the close relationship with inflammation. In this review, we highlight recently gained mechanistic insights into the maintenance and disruption of the BBB. A better understanding of the factors influencing BBB permeability could contribute to supporting promising potential therapeutic targets for protecting the BBB and the delivery of central nervous system drugs via BBB permeability interventions under pathological conditions.

Effects of Systematic Diet Education Combined with Multidisciplinary Nursing on Nutritional Status and Calcium and Phosphorus Metabolism in Patients with Diabetic Kidney Disease in Uremic Phase after Treatment with Alogliptin

Objective

To explore the effects of systematic diet education combined with multidisciplinary nursing on nutritional status and calcium and phosphorus metabolism in patients with diabetic kidney disease (DKD) in uremic phase after treatment with alogliptin.

Methods

A total of 90 DKD patients with uremia admitted to our hospital from January 2020 to January 2021 were selected as the research objects. The subjects were divided into combined group and routine group by random number table method. All patients received alogliptin medication. The combination group received systematic dietary education combined with multidisciplinary nursing after the medication, and the conventional group received conventional intervention. Serum albumin, blood calcium, and other indexes were detected between both groups after intervention.

Results

After intervention, compared with the conventional group, all nutritional indexes of the combined group were obviously higher, levels of serum phosphorus and calcium-phosphorus product of the combined group were obviously lower (P < 0.001), the incidence of hypoglycemia and hyperglycemia of the combined group was obviously lower (P < 0.05), the total compliance rate of the combined group was obviously higher (P < 0.05), and the SAS score of the combined group was obviously lower (P < 0.001).

Conclusion

With conspicuous intervention effect, systematic diet education combined with multidisciplinary nursing is a reliable method that can improve the nutritional status and levels of calcium and phosphorus metabolism, enhance treatment compliance, and reduce anxiety. Further research will help to provide a better solution for patients. This trial is registered with ChiCTR2200057011.

Protective multi‑target effects of DL‑3‑n‑butylphthalide combined with 3‑methyl‑1‑phenyl‑2‑pyrazolin‑5‑one in mice with ischemic stroke

DL-3-n-butylphthalide (NBP) and 3-methyl-1- phenyl-2-pyrazolin-5-one (edaravone) are acknowledged neuroprotective agents that protect against ischemic stroke. However, the underlying mechanisms of a combination therapy with NBP and edaravone have not yet been fully clarified. The aim of the present study was to explore whether the co-administration of NBP and edaravone had multi-target protective effects on the neurovascular unit (NVU) of mice affected by ischemic stroke. Male C57BL/6 mice were randomly divided into the following three groups: i) Sham operation control, ii) middle cerebral artery occlusion (MCAO) and reperfusion, iii) and MCAO/reperfusion with the co-administration of NBP (40 mg/kg) and edaravone (6 mg/kg) delivered via intraperitoneal injection at 0 and 4 h after reperfusion (NBP + edaravone). After ischemia and reperfusion, infarct volumes and neurological deficits were evaluated. The immunoreactivity of the NVU, comprising neurons, endothelial cells and astrocytes, was determined using immunofluorescence staining of neuronal nuclei (NeuN), platelet and endothelial cell adhesion molecule 1 (CD31) and glial fibrillary acidic protein (GFAP). Western blotting was used to detect the expression levels of apoptosis-related proteins. The infarct volume, neurological function scores and cell damage were increased in the MCAO group compared with the sham operation group. Furthermore, the MCAO mice had reduced NeuN and CD31 expression and increased GFAP expression compared with the sham group. By contrast, the NBP + edaravone group exhibited reduced cell damage and consequently lower infarct volume and neurological deficit scores compared with the MCAO group. The NBP + edaravone group exhibited increased NeuN and CD31 expression and decreased GFAP expression compared with the MCAO group. Furthermore, the expression levels of Bax and cleaved caspase-3 in the NBP + edaravone group were decreased significantly compared with the MCAO group, while the expression levels of Bcl-2 and mitochondrial cytochrome c were increased. In conclusion, the results of the present study demonstrated that NBP and edaravone effectively prevented ischemic stroke damage with multi-target protective effects. In addition, NBP + edaravone may be a promising combination therapy for ischemic stroke.

Blood-Brain Barrier Dysfunction Amplifies the Development of Neuroinflammation: Understanding of Cellular Events in Brain Microvascular Endothelial Cells for Prevention and Treatment of BBB Dysfunction

Neuroinflammation is involved in the onset or progression of various neurodegenerative diseases. Initiation of neuroinflammation is triggered by endogenous substances (damage-associated molecular patterns) and/or exogenous pathogens. Activation of glial cells (microglia and astrocytes) is widely recognized as a hallmark of neuroinflammation and triggers the release of proinflammatory cytokines, leading to neurotoxicity and neuronal dysfunction. Another feature associated with neuroinflammatory diseases is impairment of the blood-brain barrier (BBB). The BBB, which is composed of brain endothelial cells connected by tight junctions, maintains brain homeostasis and protects neurons. Impairment of this barrier allows trafficking of immune cells or plasma proteins into the brain parenchyma and subsequent inflammatory processes in the brain. Besides neurons, activated glial cells also affect BBB integrity. Therefore, BBB dysfunction can amplify neuroinflammation and act as a key process in the development of neuroinflammation. BBB integrity is determined by the integration of multiple signaling pathways within brain endothelial cells through intercellular communication between brain endothelial cells and brain perivascular cells (pericytes, astrocytes, microglia, and oligodendrocytes). For prevention of BBB disruption, both cellular components, such as signaling molecules in brain endothelial cells, and non-cellular components, such as inflammatory mediators released by perivascular cells, should be considered. Thus, understanding of intracellular signaling pathways that disrupt the BBB can provide novel treatments for neurological diseases associated with neuroinflammation. In this review, we discuss current knowledge regarding the underlying mechanisms involved in BBB impairment by inflammatory mediators released by perivascular cells.

Trelagliptin Mitigates Macrophage Infiltration by Preventing the Breakdown of the Blood-Brain Barrier in the Brain of Middle Cerebral Artery Occlusion Mice

Stroke is a significant cardiovascular disease that influences the health of human beings all over the world, especially the elderly population. It is reported that the blood-brain barrier (BBB) can be easily destroyed by stroke, which is one of the main factors responsible for macrophage infiltration and central nervous inflammation. Here, we report the protective effects of Trelagliptin against BBB injury and macrophage infiltration. Our results indicate that the infraction volume, the neurological score, and macrophage infiltration staining with CD68 were increased in middle cerebral artery occlusion (MCAO) mice but significantly reversed by treatment with Trelagliptin. Additionally, Trelagliptin reduced the permeability of the BBB by increasing the expression of the tight junction zonula occludens protein-1 (ZO-1) in the cerebral cortex. In an in vitro hypoxia model of endothelial cells, the increased migration of macrophages, enlarged permeability of endothelial monolayer, downregulation of ZO-1, and elevated expression level of CXCL1 by hypoxic conditions were all reversed by treatment with Trelagliptin in a dose-dependent manner. Our results demonstrate that Trelagliptin might mitigate macrophage infiltration by preventing the breakdown of the blood-brain barrier in the brains of MCAO mice.

NDRG2 attenuates ischemia-induced astrocyte necroptosis via the repression of RIPK1

Cerebral ischemia results in severe brain damage, and is a leading cause of death and long-term disability. Previous studies have investigated methods to activate astrocytes in order to promote repair in injured brain tissue and inhibit cell death. It has previously been shown that N-myc downstream-regulated gene 2 (NDRG2) was highly expressed in astrocytes and associated with cell activity, but the underlying mechanism is largely unknown. The present study generated NDRG2 conditional knockout (Ndrg2-/-) mice to investigate whether NDRG2 can block ischemia-induced astrocyte necroptosis by suppressing receptor interacting protein kinase 1 (RIPK1) expression. This study investigated astrocyte activity in cerebral ischemia, and identified that ischemic brain injuries could trigger RIP-dependent astrocyte necroptosis. The depletion of NDRG2 was found to accelerate permanent middle cerebral artery occlusion-induced necroptosis in the brain tissue of Ndrg2-/- mice, indicating that NDRG2 may act as a neuroprotector during cerebral ischemic injury. The present study suggested that NDRG2 attenuated astrocytic cell death via the suppression of RIPK1. The pharmacological inhibition of astrocyte necroptosis by necrostatin-1 provided neuroprotection against ischemic brain injuries after NDRG2 knockdown. Therefore, NDRG2 could be considered as a potential target for the treatment of cerebral ischemia.

Alogliptin reversed hippocampal insulin resistance in an amyloid-beta fibrils induced animal model of Alzheimer's disease

The complications of Alzheimer's disease (AD) have made the development of its treatment a challenging task. Several studies have indicated the disruption of insulin receptor substrate-1 (IRS-1) signaling during the development and progression of AD. The role of a dipeptidyl peptidase-4 (DPP-4) inhibitor on hippocampal IRS-1 signaling has not been investigated before. In this study, we evaluated the efficacy of alogliptin (DPP-4 inhibitor) on hippocampal insulin resistance and associated AD complications. In the present study, amyloid-β (1-42) fibrils were produced and administered intrahippocampally for inducing AD in Wistar rats. After 7 days of surgery, rats were treated with 10 and 20 mg/kg of alogliptin for 28 days. Morris water maze (MWM) test was performed in the last week of our experimental study. Post 24 h of final treatment, rats were euthanized and hippocampi were separated for biochemical and histopathological investigations. In-silico analysis revealed that alogliptin has a good binding affinity with Aβ and beta-secretase-1 (BACE-1). Alogliptin significantly restored cognitive functions in Aβ (1-42) fibrils injected rats during the MWM test. Alogliptin also significantly attenuated insulin level, IRS-1pS307 expression, Aβ (1-42) level, GSK-3β activity, TNF-α level and oxidative stress in the hippocampus. The histopathological analysis supported alogliptin mediated neuroprotective and anti-amyloidogenic effect. Immunohistochemical analysis also revealed a reduction in IRS-1pS307 expression after alogliptin treatment. The in-silico, behavioral, biochemical and histopathological analysis supports the protective effect of alogliptin against hippocampal insulin resistance and AD.

Neuroprotective Effects of Diabetes Drugs for the Treatment of Neonatal Hypoxia-Ischemia Encephalopathy

The perinatal period represents a time of great vulnerability for the developing brain. A variety of injuries can result in death or devastating injury causing profound neurocognitive deficits. Hypoxic-ischemic neonatal encephalopathy (HIE) remains the leading cause of brain injury in term infants during the perinatal period with limited options available to aid in recovery. It can result in long-term devastating consequences with neurologic complications varying from mild behavioral deficits to severe seizure, intellectual disability, and/or cerebral palsy in the newborn. Despite medical advances, the only viable option is therapeutic hypothermia which is classified as the gold standard but is not used, or may not be as effective in preterm cases, infection-associated cases or low resource settings. Therefore, alternatives or adjunct therapies are urgently needed. Ongoing research continues to advance our understanding of the mechanisms contributing to perinatal brain injury and identify new targets and treatments. Drugs used for the treatment of patients with type 2 diabetes mellitus (T2DM) have demonstrated neuroprotective properties and therapeutic efficacy from neurological sequelae following HIE insults in preclinical models, both alone, or in combination with induced hypothermia. In this short review, we have focused on recent findings on the use of diabetes drugs that provide a neuroprotective effect using in vitro and in vivo models of HIE that could be considered for clinical translation as a promising treatment.

Alogliptin inhibits IL-1β-induced inflammatory response in fibroblast-like synoviocytes

Excessive production of pro-inflammatory cytokines such as interleukin (IL)-1β plays an important role in the chronic inflammation in fibroblast-like synoviocytes (FLS) in rheumatoid arthritis (RA). Alogliptin, an important selective dipeptidyl peptidase-4 (DPP-4) inhibitor licensed for the treatment of type 2 diabetes, has displayed a wide range of pharmacological capacities. In the present study, we aimed to investigate whether alogliptin possessed a protective effect against IL-1β-induced insult in FLS. Our results indicate that alogliptin treatment ameliorated IL-1β-induced production of reactive oxygen species, the expression of matrix metalloproteinase-3 (MMP-3) and MMP-13, secretions of tumor necrosis factor-α (TNF-α), IL-6, and IL-8. Additionally, we found that alogliptin inhibited c-Jun N-terminal kinase (JNK)/activator protein 1 (AP-1) signaling by reducing IL-1β-induced phosphorylation of JNK, the expression of c-Jun and c-Fos, and the luciferase activity of AP-1. Importantly, alogliptin suppressed IL-1β-induced activation of IκBα/NF-κB signaling by preventing the phosphorylation and degradation of IκBα, nuclear translocation of NF-κB p65, as well as the luciferase activity of AP-1. These findings suggest that alogliptin might have therapeutic potential for the treatment of chronic inflammation in RA.

The effect and mechanism of combination of total paeony glycosides and total ligustici phenolic acids against focal cerebral ischemia

The root of Paeonia lactiflora Pall. (Chishao, CS) and Ligusticum chuanxiong Hort. (Chuanxiong, CX) were widely used as a drug pair in Chinese Medicine, and the combination of CS and CX showed a more significant inhibition on neuronal apoptosis in our previous study. In the present study, total paeony glycosides (TPGs) from CS and total ligustici phenolic acids (TLPAs) from CX were combined to evaluate the synergistic effects against focal cerebral ischemia both in vitro and in vivo. The combination of TPGs and TLPAs at 7:3 had the best anti-oxidative stress and anti-inflammatory effect on OGD-induced HUVEC. Additionally, the infarction area proportion and neuron apoptosis of rats by TPGs:TLPAs (7:3) was significantly lower than their alone in MCAO rats. Moreover, TPGs: TLPAs of 7:3 showed a more significant effect on decreasing the expression of MMP-2 and MMP-9, and increasing the protein expression or mRNA level of TIMP-1 than other combinations. The optimal ratio of TPGs and TLPAs at 7:3 could bring more remarkable protective effects against focal cerebral ischemia in MCAO rats by alleviating oxidative stress, inflammatory and neuronal apoptosis to protect the blood-brain barrier. Overall, the present study provided benefical evidence for clinical application of CS and CX as a "drug pair".

Aloin Protects Against Blood-Brain Barrier Damage After Traumatic Brain Injury in Mice

Aloin is a small-molecule drug well known for its protective actions in various models of damage. Traumatic brain injury (TBI)-induced cerebral edema from secondary damage caused by disruption of the blood-brain barrier (BBB) often leads to an adverse prognosis. Since the role of aloin in maintaining the integrity of the BBB after TBI remains unclear, we explored the protective effects of aloin on the BBB using in vivo and in vitro TBI models. Adult male C57BL/6 mice underwent controlled cortical impact injury, and mouse brain capillary endothelial bEnd.3 cells underwent biaxial stretch injury, then both received aloin treatment. In the animal experiments, we found 20 mg/kg aloin to be the optimum concentration to decrease cerebral edema, decrease disruption of the BBB, and improve neurobehavioral performance after cortical impact injury. In the cellular studies, the optimum concentration of 40 μg/mL aloin reduced apoptosis and reversed the loss of tight junctions by reducing the reactive oxygen species levels and changes in mitochondrial membrane potential after stretch injury. The mechanisms may be that aloin downregulates the phosphorylation of p38 mitogen-activated protein kinase, the activation of p65 nuclear factor-kappa B, and the ratios of B cell lymphoma (Bcl)-2-associated X protein/Bcl-2 and cleaved caspase-3/caspase-3. We conclude that aloin exhibits these protective effects on the BBB after TBI through its anti-oxidative stress and anti-apoptotic properties in mouse brain capillary endothelial cells. Aloin may thus be a promising therapeutic drug for TBI.

Inhibition of TIM-4 protects against cerebral ischaemia-reperfusion injury

TIM‐4 plays an important role in ischaemia‐reperfusion injury of liver and kidney; however, the effects of TIM‐4 on cerebral ischaemia‐reperfusion injury (IRI) are unknown. The purpose of the present study was to investigate the potential role of TIM‐4 in experimental brain ischaemia‐reperfusion injury. In this study, cerebral ischaemia reperfusion was induced by transient middle cerebral artery occlusion (MCAO) for 1 hour in C57/BL6 mice. The TIM‐4 expression was detected in vivo or vitro by real‐time quantitative polymerase chain reaction, Western blot and flow cytometric analysis. In vivo, the administration of anti‐TIM‐4 antibodies significantly suppressed apoptosis, inhibited inflammatory cells and enhanced anti‐inflammatory responses. In vitro, activated microglia exhibited reduced cellular proliferation and induced IRI injury when co‐cultured with neurons; these effects were inhibited by anti‐TIM‐4 antibody treatment. Similarly, microglia transfected with TIM‐4 siRNA and stimulated by LPS + IFN‐γ alleviated the TIM‐4‐mediated damage to neurons. Collectively, our data indicate that the inhibition of TIM‐4 can improve the inflammatory response and exerts a protective effect in cerebral ischaemia‐reperfusion injury.

Of mice and men: incretin actions in the central nervous system

Incretins have risen to the forefront of therapies for obesity and related metabolic complications, primarily because of their efficacy and relatively few side effects. Importantly, their efficacy in altering energy balance and decreasing body weight is apparently through actions in the central nervous system (CNS); the latter may have implications beyond obesity per se, i.e. in other disease states associated with obesity including CNS-related disorders. Here, we first describe the role of the CNS in energy homeostasis and then the current state of knowledge in terms of incretin physiology, pathophysiology and efficacy in preclinical and clinical studies. In the future, more clinical studies are needed to fully map mechanistic pathways underlying incretin actions and outcomes in the human CNS. Additionally, future research will likely lead to the discovery of additional novel incretins and/or more efficacious medications with less side effects through the improvement of current compounds with properties that would allow them to have more favorable pharmacokinetic and pharmacodynamic profiles and/or by combining known and novel incretins into safe and more efficacious combination therapies leading ultimately to more tangible benefits for our patients.

Sijunzi decoction may decrease apoptosis via stabilization of the extracellular matrix following cerebral ischaemia-reperfusion in rats

Neurons undergo degeneration, apoptosis and death due to ischaemic stroke. The present study investigated the effect of Sijunzi decoction (SJZD), a type of traditional Chinese medicine known as invigorating spleen therapy, on anoikis (a type of apoptosis) in rat brains following cerebral ischaemia-reperfusion. Rats were randomly divided into sham, model, nimodipine and SJZD low/medium/high dose groups. A middle cerebral artery occlusion model was established. Neurobehavioural scores were evaluated after administration for 14 days using a five-grade scale. Blood-brain barrier permeability and apoptotic rate were detected using Evans blue (EB) extravasation and TUNEL staining, respectively. Tissue inhibitor of metalloproteinase 1 (TIMP-1), matrix metalloproteinase 9 (MMP-9) and collagen IV (COL IV) were determined using immunohistochemistry. Neurobehavioural scores decreased remarkably in all SJZD and nimodipine groups compared to the model group (P<0.05). Compared with the sham group, EB extravasation was higher in the model group (P<0.01). The amount of EB extravasation decreased in the SJZD high dose and nimodipine groups compared to the model group (P<0.01), and extravasation in the SJZD high dose group was lower than the SJZD low and medium dose groups (P<0.01). TIMP-1 and MMP-9 expression and apoptotic rate increased, but COL IV decreased significantly in the hippocampus of the model group compared to the sham group (P<0.01). TIMP-1 and COL IV expression increased significantly and MMP-9 and apoptotic rate decreased remarkably in all SJZD and nimodipine groups compared to the model group (P<0.01). TIMP-1 and COL IV expression decreased, but MMP-9 expression and apoptotic rate increased in the SJZD low and medium dose groups compared to the SJZD high dose group (P<0.01). SJZD rescued neurons and improved neurobehavioural function in rats following cerebral ischaemia-reperfusion, especially when used at a high dose. The mechanism may be related to protection of the extracellular matrix followed by anti-apoptotic effects.

An up-to-date evaluation of alogliptin benzoate for the treatment of type 2 diabetes

Introduction: A growth in the market for anti-diabetic drugs, along with an ever-increasing population suffering from type 2 diabetes mellitus (T2DM), requires a critical re-evaluation of anti-diabetic drugs used for a long time, in order to provide up-to-date practical prescribing information for clinicians. Alogliptin benzoate was firstly approved in 2010 in Japan for T2DM, both as a monotherapy or in combination with other anti-diabetic drugs. Areas covered: This article provides a comprehensive review of the latest data on alogliptin benzoate, including hypoglycemic activity and safety. Expert opinion: The cumulative evidence for alogliptin benzoate is robust with regards to glycemic efficacy and safety. Low hypoglycemia risks and weight changes support its consideration as a first-line medication for T2DM, either as a monotherapy or in combination therapy with other anti-diabetic drugs such as metformin. Ongoing trials will look to better analyze and address its safety and efficacy in pediatric patients and expand our clinical knowledge of this medication.

Antidiabetic treatment on memory and spatial learning: From the pancreas to the neuron

The detrimental effects of constant hyperglycemia on neural function have been quantitatively and qualitatively evaluated in the setting of diabetes mellitus. Some of the hallmark features of diabetic encephalopathy (DE) are impaired synaptic adaptation and diminished spatial learning capacity. Chronic and progressive cognitive dysfunction, perpetuated by several positive feedback mechanisms in diabetic subjects, facilitates the development of early-onset dementia and Alzheimer's disease. Despite the numerous clinical manifestations of DE having been described in detail and their pathophysiological substrate having been elucidated in both type 1 and type 2 diabetes mellitus, an effective therapeutic approach is yet to be proposed. Therefore, the aim of this review is to summarize the growing body of evidence concerning the effect of current antidiabetic treatment options on diabetic and non-DE.