Protective effect of Tat fused HPCA protein on neuronal cell death caused by ischemic injury.

Background: Bain ischemia is a disease that occurs for various reasons, induces reactive oxygen species (ROS), and causes fatal damage to the nervous system. Protective effect of HPCA on ischemic injury has not been extensively studied despite its significance in regulating calcium homeostasis and promoting neuronal survival in CA1 region of the brain. Objective: We investigate the role of HPCA in ischemic injury using a cell-permeable Tat peptide fused HPCA protein (Tat-HPCA). Methods: Western blot analysis determined the penetration of Tat-HPCA into HT-22 cells and apoptotic signaling pathways. 5-CFDA, AM, DCF-DA, and TUNEL staining confirmed intracellular ROS production and DNA damage. The intracellular Ca2+ was measured in primary cultured neurons treated with H2O2. Protective effects were examined using immunohistochemistry and cognitive function tests by passive avoidance test and 8-arm radial maze test. Results: Tat-HPCA effectively penetrated into HT-22 cells and inhibited H2O2-induced apoptosis, oxidative stress, and DNA fragmentation. It also effectively inhibited phosphorylation of JNK and regulated the activation of Caspase, Bax, Bcl-2, and PARP, leading to inhibition of apoptosis. Moreover, Ca2+ concentration decreased in cells treated with Tat-HPCA in primary cultured neurons. In an animal model of ischemia, Tat-HPCA effectively penetrated the hippocampus, inhibited cell death, and regulated activities of astrocytes and microglia. Additionally, Cognitive function tests show that Tat-HPCA improves neurobehavioral outcomes after cerebral ischemic injury. Conclusion: These results suggest that Tat-HPCA might have potential as a therapeutic agent for treating oxidative stress-related diseases induced by ischemic injury, including ischemia.

Tat-CIAPIN1 Prevents Pancreatic ß-Cell Death in hIAPP-Induced RINm5F Cells and T2DM Animal Model.

It is well known that the cytokine-induced apoptosis inhibitor 1 (CIAPIN1) protein plays an important role in biological progresses as an anti-apoptotic protein. Human islet amyloid peptide (hIAPP), known as amylin, is caused to pancreatic ß-cell death in type 2 diabetes mellitus (T2DM). However, the function of CIAPIN1 protein on T2DM is not yet well studied. Therefore, we investigated the effects of CIAPIN1 protein on a hIAPP-induced RINm5F cell and T2DM animal model induced by a high-fat diet (HFD) and streptozotocin (STZ). The Tat-CIAPIN1 protein reduced the activation of mitogen-activated protein kinase (MAPK) and regulated the apoptosis-related protein expression levels including COX-2, iNOS, Bcl-2, Bax, and Caspase-3 in hIAPP-induced RINm5F cells. In a T2DM mice model, the Tat-CIAPIN1 protein ameliorated the pathological changes of pancreatic ß-cells and reduced the fasting blood glucose, body weight and hemoglobin Alc (HbAlc) levels. In conclusion, the Tat-CIAPIN1 protein showed protective effects against T2DM by protection of ß-cells via inhibition of hIAPP toxicity and by regulation of a MAPK signal pathway, suggesting CIAPIN1 protein can be a therapeutic protein drug candidate by beneficial regulation of T2DM.

Tat-RAN attenuates brain ischemic injury in hippocampal HT-22 cells and ischemia animal model.

Oxidative stress plays a key role in the pathogenesis of neuronal injury, including ischemia. Ras-related nuclear protein (RAN), a member of the Ras superfamily, involves in a variety of biological roles, such as cell division, proliferation, and signal transduction. Although RAN reveals antioxidant effect, its precise neuroprotective mechanisms are still unclear. Therefore, we investigated the effects of RAN on HT-22 cell which were exposed to H2O2-induced oxidative stress and ischemia animal model by using the cell permeable Tat-RAN fusion protein. We showed that Tat-RAN transduced into HT-22 cells, and markedly inhibited cell death, DNA fragmentation, and reactive oxygen species (ROS) generation under oxidative stress. This fusion protein also controlled cellular signaling pathways, including mitogen-activated protein kinases (MAPKs), NF-κB, and apoptosis (Caspase-3, p53, Bax and Bcl-2). In the cerebral forebrain ischemia animal model, Tat-RAN significantly inhibited both neuronal cell death, and astrocyte and microglia activation. These results indicate that RAN significantly protects against hippocampal neuronal cell death, suggesting Tat-RAN will help to develop the therapies for neuronal brain diseases including ischemic injury.

Protective effects of cell permeable Tat-PIM2 protein on oxidative stress induced dopaminergic neuronal cell death.

Background: Oxidative stress is considered as one of the main causes of Parkinson's disease (PD), however the exact etiology of PD is still unknown. Although it is known that Proviral Integration Moloney-2 (PIM2) promotes cell survival by its ability to inhibit formation of reactive oxygen species (ROS) in the brain, the precise functional role of PIM2 in PD has not been fully studied yet. Objective: We investigated the protective effect of PIM2 against apoptosis of dopaminergic neuronal cells caused by oxidative stress-induced ROS damage by using the cell permeable Tat-PIM2 fusion protein in vitro and in vivo. Methods: Transduction of Tat-PIM2 into SH-SY5Y cells and apoptotic signaling pathways were determined by Western blot analysis. Intracellular ROS production and DNA damage was confirmed by DCF-DA and TUNEL staining. Cell viability was determined by MTT assay. PD animal model was induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and protective effects were examined using immunohistochemistry. Results: Transduced Tat-PIM2 inhibited the apoptotic caspase signaling and reduced the production of ROS induced by 1-methyl-4-phenylpyridinium (MPP+) in SH-SY5Y cells. Furthermore, we confirmed that Tat-PIM2 transduced into the substantia nigra (SN) region through the blood-brain barrier and this protein protected the Tyrosine hydroxylase-positive cells by observation of immunohistostaining. Tat-PIM2 also regulated antioxidant biomolecules such as SOD1, catalase, 4-HNE, and 8-OHdG which reduce the formation of ROS in the MPTP-induced PD mouse model. Conclusion: These results indicated that Tat-PIM2 markedly inhibited the loss of dopaminergic neurons by reducing ROS damage, suggesting that Tat-PIM2 might be a suitable therapeutic agent for PD.

Tat-GSTpi Inhibits Dopaminergic Cells against MPP+-Induced Cellular Damage via the Reduction of Oxidative Stress and MAPK Activation.

Glutathione S-transferase pi (GSTpi) is a member of the GST family and plays many critical roles in cellular processes, including anti-oxidative and signal transduction. However, the role of anti-oxidant enzyme GSTpi against dopaminergic neuronal cell death has not been fully investigated. In the present study, we investigated the roles of cell permeable Tat-GSTpi fusion protein in a SH-SY5Y cell and a Parkinson's disease (PD) mouse model. In the 1-methyl-4-phenylpyridinium (MPP+)-exposed cells, Tat-GSTpi protein decreased DNA damage and reactive oxygen species (ROS) generation. Furthermore, this fusion protein increased cell viability by regulating MAPKs, Bcl-2, and Bax signaling. In addition, Tat-GSTpi protein delivered into the substantia nigra (SN) of mice brains protected dopaminergic neuronal cell death in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD animal model. Our results indicate that the Tat-GSTpi protein inhibited cell death from MPP+- and MPTP-induced damage, suggesting that it plays a protective role during the loss of dopaminergic neurons in PD and that it could help to identify the mechanism responsible for neurodegenerative diseases, including PD.

Protective Effects of PEP-1-GSTA2 Protein in Hippocampal Neuronal Cell Damage Induced by Oxidative Stress.

Glutathione S-transferase alpha 2 (GSTA2), a member of the glutathione S-transferase family, plays the role of cellular detoxification against oxidative stress. Although oxidative stress is related to ischemic injury, the role of GSTA2 against ischemia has not been elucidated. Thus, we studied whether GSTA2 prevents ischemic injury by using the PEP-1-GSTA2 protein which has a cell-permeable protein transduction domain. We revealed that cell-permeable PEP-1-GSTA2 transduced into HT-22 cells and markedly protected cell death via the inhibition of reactive oxygen species (ROS) production and DNA damage induced by oxidative stress. Additionally, transduced PEP-1-GSTA2 promoted mitogen-activated protein kinase (MAPK), and nuclear factor-kappaB (NF-κB) activation. Furthermore, PEP-1-GSTA2 regulated Bcl-2, Bax, cleaved Caspase-3 and -9 expression protein levels. An in vivo ischemic animal model, PEP-1-GSTA2, markedly prevented the loss of hippocampal neurons and reduced the activation of microglia and astrocytes. These findings indicate that PEP-1-GSTA2 suppresses hippocampal cell death by regulating the MAPK and apoptotic signaling pathways. Therefore, we suggest that PEP-1-GSTA2 will help to develop the therapies for oxidative-stress-induced ischemic injury.

Protective effect of GK2 fused BLVRA protein against oxidative stress-induced dopaminergic neuronal cell damage.

It is well known that oxidative stress is highly associated with Parkinson's disease (PD), and biliverdin reductase A (BLVRA) is known to have antioxidant properties against oxidative stress. In this study, we developed a novel N-acetylgalactosamine kinase (GK2) protein transduction domain (PTD) derived from adenosine A2A and fused with BLVRA to determine whether the GK2-BLVRA fusion protein could protect dopaminergic neuronal cells (SH-SY5Y) from oxidative stress in vitro and in vivo using a PD animal model. GK2-BLVRA was transduced into various cells, including SH-SY5Y cells, without cytotoxic effects, and this fusion protein protected SH-SY5Y cells and reduced reactive oxygen species production and DNA damage after 1-methyl-4-phenylpyridinium (MPP+ ) exposure. GK2-BLVRA suppressed mitogen-activated protein kinase (MAPK) activation and modulated apoptosis-related protein (Bcl-2, Bax, cleaved Caspase-3 and -9) expression levels. In the PD animal model, GK2-BLVRA transduced into the substantia nigra crossed the blood-brain barrier and markedly reduced dopaminergic neuronal cell death in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced animals. These results indicate that our novel PTD GK-2 is useful for the transduction of protein, and GK2-BLVRA exhibits a beneficial effect against dopaminergic neuronal cell death in vitro and in vivo, suggesting that BLVRA can be used as a therapeutic agent for PD.

Tat-Thioredoxin-like protein 1 attenuates ischemic brain injury by regulation of MAPKs and apoptosis signaling.

Thioredoxin-like protein 1 (TXNL1), one of the thioredoxin superfamily known as redox-regulator, plays an essential in maintaining cell survival via various antioxidant and anti-apoptotic mechanisms. It is well known that relationship between ischemia and oxidative stress, however, the role of TXNL1 protein in ischemic damage has not been fully investigated. In the present study, we aimed to determine the protective role of TXNL1 against on ischemic injury in vitro and in vivo using cell permeable Tat-TXNL1 fusion protein. Transduced Tat-TXNL1 inhibited ROS production and cell death in H2O2-exposed hippocampal neuronal (HT-22) cells and modulated MAPKs and Akt activation, and pro-apoptotic protein expression levels in the cells. In an ischemia animal model, Tat-TXNL1 markedly decreased hippocampal neuronal cell death and the activation of astrocytes and microglia. These findings indicate that cell permeable Tat-TXNL1 protects against oxidative stress in vitro and in vivo ischemic animal model. Therefore, we suggest Tat-TXNL1 can be a potential therapeutic protein for ischemic injury. [BMB Reports 2023; 56(4): 234-239].

Tat-thioredoxin 1 reduces inflammation by inhibiting pro-inflammatory cytokines and modulating MAPK signaling.

Thioredoxin 1 (Trx1) serves a central role in redox homeostasis. It is involved in numerous other processes, including oxidative stress and apoptosis. However, to the best of our knowledge, the role of Trx1 in inflammation remains to be explored. The present study investigated the function and mechanism of cell permeable fused Tat-Trx1 protein in macrophages and a mouse model. Transduction levels of Tat-Trx1 were determined via western blotting. Cellular distribution of transduced Tat-Trx1 was determined by fluorescence microscopy. 2',7'-Dichlorofluorescein diacetate and TUNEL staining were performed to determine the production of reactive oxygen species and DNA fragmentation. Protein and gene expression were measured by western blotting and reverse transcription-quantitative PCR (RT-qPCR), respectively. Effects of skin inflammation were determined using hematoxylin and eosin staining, changes in ear weight and ear thickness, and RT-qPCR in ear edema animal models. Transduced Tat-Trx1 inhibited lipopolysaccharide-induced cytotoxicity and activation of NF-κB, MAPK and Akt. Additionally, Tat-Trx1 markedly reduced the production of inducible nitric oxide synthase, cyclooxygenase-2, IL-1ß, IL-6 and TNF-α in macrophages. In a 12-O-tetradecanoylphorbol-13-acetate-induced mouse model, Tat-Trx1 reduced inflammatory damage by inhibiting inflammatory mediator and cytokine production. Collectively, these results demonstrated that Tat-Trx1 could exert anti-inflammatory effects by inhibiting the production of pro-inflammatory mediators and cytokines and by modulating MAPK signaling. Therefore, Tat-Trx1 may be a useful therapeutic agent for diseases induced by inflammatory damage.

PEP-1-GLRX1 Reduces Dopaminergic Neuronal Cell Loss by Modulating MAPK and Apoptosis Signaling in Parkinson's Disease.

Parkinson's disease (PD) is characterized mainly by the loss of dopaminergic neurons in the substantia nigra (SN) mediated via oxidative stress. Although glutaredoxin-1 (GLRX1) is known as one of the antioxidants involved in cell survival, the effects of GLRX1 on PD are still unclear. In this study, we investigated whether cell-permeable PEP-1-GLRX1 inhibits dopaminergic neuronal cell death induced by 1-methyl-4-phenylpyridinium (MPP+) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). We showed that PEP-1-GLRX1 protects cell death and DNA damage in MPP+-exposed SH-SY5Y cells via the inhibition of MAPK, Akt, and NF-κB activation and the regulation of apoptosis-related protein expression. Furthermore, we found that PEP-1-GLRX1 was delivered to the SN via the blood-brain barrier (BBB) and reduced the loss of dopaminergic neurons in the MPTP-induced PD model. These results indicate that PEP-1-GLRX1 markedly inhibited the loss of dopaminergic neurons in MPP+- and MPTP-induced cytotoxicity, suggesting that this fusion protein may represent a novel therapeutic agent against PD.

Transduced Tat-PRAS40 prevents dopaminergic neuronal cell death through ROS inhibition and interaction with 14-3-3σ protein.

Proline rich Akt substrate (PRAS40) is a component of mammalian target of rapamycin complex 1 (mTORC1) and activated mTORC1 plays important roles for cellular survival in response to oxidative stress. However, the roles of PRAS40 in dopaminergic neuronal cell death have not yet been examined. Here, we examined the roles of Tat-PRAS40 in MPP+- and MPTP-induced dopaminergic neuronal cell death. Our results showed that Tat-PRAS40 effectively transduced into SH-SY5Y cells and inhibited DNA damage, ROS generation, and apoptotic signaling in MPP+-induced SH-SY5Y cells. Further, these protective mechanisms of Tat-PRAS40 protein display through phosphorylation of Tat-PRAS40, Akt and direct interaction with 14-3-3σ protein, but not via the mTOR-dependent signaling pathway. In a Parkinson's disease animal model, Tat-PRAS40 transduced into dopaminergic neurons in mouse brain and significantly protected against dopaminergic cell death by phosphorylation of Tat-PRAS40, Akt and interaction with 14-3-3σ protein. In this study, we demonstrated for the first time that Tat-PRAS40 directly protects against dopaminergic neuronal cell death. These results indicate that Tat-PRAS40 may provide a useful therapeutic agent against oxidative stress-induced dopaminergic neuronal cell death, which causes diseases such as PD.

Tat-CIAPIN1 protein prevents against cytokine-induced cytotoxicity in pancreatic RINm5F ß-cells.

Cytokines activate inflammatory signals and are major mediators in progressive ß-cell damage, which leads to type 1 diabetes mellitus. We recently showed that the cell-permeable Tat-CIAPIN1 fusion protein inhibits neuronal cell death induced by oxidative stress. However, how the Tat-CIAPIN1 protein affects cytokine-induced ß-cell damage has not been investigated yet. Thus, we assessed whether the Tat-CIAPIN1 protein can protect RINm5F ß-cells against cytokine-induced cytotoxicity. In cytokine-exposed RINm5F ß-cells, the transduced Tat-CIAPIN1 protein elevated cell survivals and reduced reactive oxygen species (ROS) and DNA fragmentation levels. The Tat-CIAPIN1 protein reduced mitogen-activated protein kinases (MAPKs) and NF-κB activation levels and elevated Bcl-2 protein, whereas Bax and cleaved Caspase-3 proteins were decreased by this fusion protein. Thus, the protection of RINm5F ß-cells by the Tat-CIAPIN1 protein against cytokine-induced cytotoxicity can suggest that the Tat-CIAPIN1 protein might be used as a therapeutic inhibitor against RINm5F ß-cell damage. [BMB Reports 2021; 54(9): 458-463].

Effect of Korean Red Ginseng on metabolic syndrome.

Metabolic syndrome (MS) refers to a clustering of at least three of the following medical conditions: high blood pressure, abdominal obesity, hyperglycemia, low high-density lipoprotein level, and high serum triglycerides. MS is related to a wide range of diseases which includes obesity, diabetes, insulin resistance, cardiovascular disease, dyslipidemia, or non-alcoholic fatty liver disease. There remains an ongoing need for improved treatment strategies for MS. The most important risk factors are dietary pattern, genetics, old age, lack of exercise, disrupted biology, medication usage, and excessive alcohol consumption, but pathophysiology of MS has not been completely identified. Korean Red Ginseng (KRG) refers to steamed/dried ginseng, traditionally associated with beneficial effects such as anti-inflammation, anti-fatigue, anti-obesity, anti-oxidant, and anti-cancer effects. KRG has been often used in traditional medicine to treat multiple metabolic conditions. This paper summarizes the effects of KRG in MS and related diseases such as obesity, cardiovascular disease, insulin resistance, diabetes, dyslipidemia, or non-alcoholic fatty liver disease based on experimental research and clinical studies.

Effect of Korea red ginseng on nonalcoholic fatty liver disease: an association of gut microbiota with liver function.

BACKGROUND: Korea Red Ginseng (KRG) has been used as remedies with hepato-protective effects in liver-related condition. Microbiota related gut-liver axis plays key roles in the pathogenesis of chronic liver disease. We evaluated the effect of KRG on gut-liver axis in patients with nonalcoholic statohepatitis by the modulation of gut-microbiota. METHODS: A total of 94 patients (KRG: 45 and placebo: 49) were prospectively randomized to receive KRG (2,000 mg/day, ginsenoside Rg1+Rb1+Rg3 4.5mg/g) or placebo during 30 days. Liver function test, cytokeraton 18, and fatigue score were measured. Gut microbiota was analyzed by MiSeq systems based on 16S rRNA genes. RESULTS: In KRG group, the mean levels (before vs. after) of aspartate aminotransferase (53 ± 19 vs. 45 ± 23 IU/L), alanine aminotransferase (75 ± 40 vs. 64 ± 39 IU/L) and fatigue score (33 ± 13 vs. 26 ± 13) were improved (p < 0.05). In placebo group, only fatigue score (34 ± 13 vs. 31 ± 15) was ameliorated (p < 0.05). The changes of phyla were not statistically significant on both groups. In KRG group, increased abundance of Lactobacillus was related with improved alanine aminotransferase level and increased abundance of Clostridium and Intestinibacter was associated with no improvement after KRG supplementation. In placebo group, increased abundance of Lachnospiraceae could be related with aggravation of liver enzyme (p < 0.05). CONCLUSION: KRG effectively improved liver enzymes and fatigue score by modulating gut-microbiota in patients with fatty liver disease. Further studies are needed to understand the mechanism of improvement of nonalcoholic steatohepatitis. CLNICALTRIALSGOV: NCT03945123 (www.ClinicalTrials.gov).

Protective Role of Transduced Tat-Thioredoxin1 (Trx1) against Oxidative Stress-Induced Neuronal Cell Death via ASK1-MAPK Signal Pathway.

Oxidative stress plays a crucial role in the development of neuronal disorders including brain ischemic injury. Thioredoxin 1 (Trx1), a 12 kDa oxidoreductase, has anti-oxidant and anti-apoptotic functions in various cells. It has been highly implicated in brain ischemic injury. However, the protective mechanism of Trx1 against hippocampal neuronal cell death is not identified yet. Using a cell permeable Tat-Trx1 protein, protective mechanism of Trx1 against hydrogen peroxide-induced cell death was examined using HT-22 cells and an ischemic animal model. Transduced Tat-Trx1 markedly inhibited intracellular ROS levels, DNA fragmentation, and cell death in H2O2-treatment HT-22 cells. Tat-Trx1 also significantly inhibited phosphorylation of ASK1 and MAPKs in signaling pathways of HT-22 cells. In addition, Tat-Trx1 regulated expression levels of Akt, NF-κB, and apoptosis related proteins. In an ischemia animal model, Tat-Trx1 markedly protected hippocampal neuronal cell death and reduced astrocytes and microglia activation. These findings indicate that transduced Tat-Trx1 might be a potential therapeutic agent for treating ischemic injury.

Tat­aldose reductase prevents dopaminergic neuronal cell death by inhibiting oxidative stress and MAPK activation.

Aldose reductase (AR) is known to detoxify aldehydes and prevent oxidative stress. Although AR exerts antioxidant effects, the role of AR in Parkinson's disease (PD) remains unclear. The objective of the present study was to investigate the protective effects of AR protein against 1­methyl­4­phenylpyridinium (MPP+)­induced SH­SY5Y cell death and 1­methyl­4­phenyl­1,2,3,6­tetrahydropyridine (MPTP)­induced PD in a mouse model using the cell permeable Tat­AR fusion protein. The results revealed that when Tat­AR protein was transduced into SH­SY5Y cells, it markedly protected the cells against MPP+­induced death and DNA fragmentation. It also reduced the activation of mitogen-activated protein kinase (MAPKs) and regulated the expression levels of Bcl­2, Bax and caspase­3. Immunohistochemical analysis revealed that when Tat­AR protein was transduced into the substantia nigra (SN) of mice with PD, it markedly inhibited dopaminergic neuronal cell death. Therefore, Tat­AR may be useful as a therapeutic protein for PD.

Lactobacillus attenuates progression of nonalcoholic fatty liver disease by lowering cholesterol and steatosis.

BACKGROUND/AIMS: Nonalcoholic fatty liver disease (NAFLD) is closely related to gut-microbiome. There is a paucity of research on which strains of gut microbiota affect the progression of NAFLD. This study explored the NAFLD-associated microbiome in humans and the role of Lactobacillus in the progression of NAFLD in mice. METHODS: The gut microbiome was analyzed via next-generation sequencing in healthy people (n=37) and NAFLD patients with elevated liver enzymes (n=57). Six-week-old male C57BL/6J mice were separated into six groups (n=10 per group; normal, Western, and four Western diet + strains [109 colony-forming units/g for 8 weeks; L. acidophilus, L. fermentum, L. paracasei, and L. plantarum]). Liver/body weight ratio, liver pathology, serum analysis, and metagenomics in the mice were examined. RESULTS: Compared to healthy subjects (1.6±4.3), NAFLD patients showed an elevated Firmicutes/Bacteroidetes ratio (25.0±29.0) and a reduced composition of Akkermansia and L. murinus (P<0.05). In the animal experiment, L. acidophilus group was associated with a significant reduction in liver/body weight ratio (5.5±0.4) compared to the Western group (6.2±0.6) (P<0.05). L. acidophilus (41.0±8.6), L. fermentum (44.3±12.6), and L. plantarum (39.0±7.6) groups showed decreased cholesterol levels compared to the Western group (85.7±8.6) (P<0.05). In comparison of steatosis, L. acidophilus (1.9±0.6), L. plantarum (2.4±0.7), and L. paracasei (2.0±0.9) groups showed significant improvement of steatosis compared to the Western group (2.6±0.5) (P<0.05). CONCLUSION: Ingestion of Lactobacillus, such as L. acidophilus, L. fermentum, and L. plantarum, ameliorates the progression of nonalcoholic steatosis by lowering cholesterol. The use of Lactobacillus can be considered as a useful strategy for the treatment of NAFLD.

Tat-indoleamine 2,3-dioxygenase 1 elicits neuroprotective effects on ischemic injury.

It is well known that oxidative stress participates in neuronal cell death caused production of reactive oxygen species (ROS). The increased ROS is a major contributor to the development of ischemic injury. Indoleamine 2,3-dioxygenase 1 (IDO-1) is involved in the kynurenine pathway in tryptophan metabolism and plays a role as an anti-oxidant. However, whether IDO-1 would inhibit hippocampal cell death is poorly known. Therefore, we explored the effects of cell permeable Tat-IDO-1 protein against oxidative stress-induced HT-22 cells and in a cerebral ischemia/reperfusion injury model. Transduced Tat-IDO-1 reduced cell death, ROS production, and DNA fragmentation and inhibited mitogen-activated protein kinases (MAPKs) activation in H2O2 exposed HT-22 cells. In the cerebral ischemia/ reperfusion injury model, Tat-IDO-1 transduced into the brain and passing by means of the blood-brain barrier (BBB) significantly prevented hippocampal neuronal cell death. These results suggest that Tat-IDO-1 may present an alternative strategy to improve from the ischemic injury. [BMB Reports 2020; 53(11): 582-587].

Tat-Biliverdin Reductase A Exerts a Protective Role in Oxidative Stress-Induced Hippocampal Neuronal Cell Damage by Regulating the Apoptosis and MAPK Signaling.

Reactive oxygen species (ROS) is major risk factor in neuronal diseases including ischemia. Although biliverdin reductase A (BLVRA) plays a pivotal role in cell survival via its antioxidant function, its role in hippocampal neuronal (HT-22) cells and animal ischemic injury is not clearly understood yet. In this study, the effects of transducible fusion protein Tat-BLVRA on H2O2-induced HT-22 cell death and in an animal ischemia model were investigated. Transduced Tat-BLVRA markedly inhibited cell death, DNA fragmentation, and generation of ROS. Transduced Tat-BLVRA inhibited the apoptosis and mitogen activated protein kinase (MAPK) signaling pathway and it passed through the blood-brain barrier (BBB) and significantly prevented hippocampal cell death in an ischemic model. These results suggest that Tat-BLVRA provides a possibility as a therapeutic molecule for ischemia.

Lactobacillus and Pediococcus ameliorate progression of non-alcoholic fatty liver disease through modulation of the gut microbiome.

Targeting the gut-liver axis by modulating the gut-microbiome can be a promising therapeutic approach in nonalcoholic fatty liver disease (NAFLD). The aim of this study was to evaluate the effects of single species and a combination of Lactobacillus and Pediococcus in NAFLD mice model. Six-week male C57BL/6J mice were divided into 9 groups (n = 10/group; normal, Western diet, and 7 Western diet-strains [109 CFU/g, 8 weeks]). The strains used were L. bulgaricus, L. casei, L. helveticus, P. pentosaceus KID7, and three combinations (1: L. casei+L. helveticus, 2: L. casei+L. helveticus+P. pentosaceus KID7, and 3: L. casei+L. helveticus+L. bulgaricus). Liver/Body weight ratio, serum and stool analysis, liver pathology, and metagenomics by 16S rRNA-sequencing were examined. In the liver/body ratio, L. bulgaricus (5.1 ± 0.5), L. helveticus (5.2 ± 0.4), P. pentosaceus KID7 (5.5 ± 0.5), and combination1 and 2 (4.2 ± 0.6 and 4.8 ± 0.7) showed significant reductions compared with Western (6.2 ± 0.6)(p < 0.001). In terms of cholesterol and steatosis/inflammation/NAFLD activity, all groups except for L. casei were associated with an improvement (p < .05). The elevated level of tumor necrosis factor-α/interleukin-1ß (pg/ml) in Western (65.8 ± 7.9/163.8 ± 12.2) was found to be significantly reduced in L. bulgaricus (24.2 ± 1.0/58.9 ± 15.3), L. casei (35.6 ± 2.1/62.9 ± 6.0), L. helveticus (43.4 ± 3.2/53.6 ± 7.5), and P. pentosaceus KID7 (22.9 ± 3.4/59.7 ± 12.2)(p < 0.01). Cytokines were improved in the combination groups. In metagenomics, each strains revealed a different composition and elevated Firmicutes/Bacteroidetes ratio in the western (47.1) was decreased in L. bulgaricus (14.5), L. helveticus (3.0), and P. pentosaceus KID7 (13.3). L. bulgaricus, L. casei, L. helveticus, and P. pentosaceus KID7 supplementation can improve NAFLD-progression by modulating gut-microbiome and inflammatory pathway.