Lobeglitazone Exerts Anti-Inflammatory Effect in Lipopolysaccharide-Induced Bone-Marrow Derived Macrophages

Lobeglitazone and Its Therapeutic Benefits: A Review

Lobeglitazone is a newer oral hypoglycemic agent that has been tested in type 2 diabetes mellitus (T2DM). We aim to conduct a narrative review to find out the therapeutic benefits of lobeglitazone in patients with T2DM. We scientifically searched the electronic database of PubMed from inception until September 12, 2023, using Medical Subject Heading (MeSH) keywords. Additionally, we searched for pre-clinical trials related to lobeglitazone. We retrieved all available results of phase 1 to phase 3 studies of lobeglitazone in T2DM. Subsequently, we reviewed the results narratively. Three double-blind, randomized, placebo-controlled studies and a phase 3 trial of lobeglitazone showed that 0.5 mg daily dose exhibits effective therapeutic activity in glycemic, lipid, and hepatic control, and is also used as a secondary treatment in non-alcoholic fatty liver disease. Lobeglitazone exhibits as much antidiabetic activity as other thiazolidinediones such as pioglitazone and rosiglitazone. Side effects of lobeglitazone included peripheral edema, weight gain, and bone mineral density, which did not require hospitalization for these effects. This article highlights the pharmacological, pre-clinical, clinical, and safety pharmacology of novel thiazolidinedione lobeglitazone.

Anti-Inflammatory Effects of Tegoprazan in Lipopolysaccharide-Stimulated Bone-Marrow-Derived Macrophages

The purpose of this study was to investigate the anti-inflammatory effect of tegoprazan (TEGO) in lipopolysaccharide (LPS)-stimulated bone-marrow-derived macrophages (BMMs). To this end, compared to methylprednisolone (MP; positive control), we evaluated whether TEGO effectively differentiates LPS-stimulated BMMs into M2-phenotype macrophages. Moreover, the expression of pro- and anti-inflammatory cytokines genes influenced by TEGO was measured using quantitative real-time polymerase chain reaction (qRT-PCR) analysis. TEGO was found to reduce nitric oxide (NO) production in BMMs significantly. In addition, TEGO significantly decreased and increased the gene expression levels of pro-inflammatory and anti-inflammatory cytokines, respectively. In addition, we evaluated the phosphorylated values of the extracellular signal-regulatory kinase (ERK) and p38 in the mitogen-activated protein (MAP) kinase signaling pathway through Western blotting. TEGO significantly reduced the phosphorylated values of the ERK and p38. In other words, TEGO suppressed the various pro-inflammatory responses in LPS-induced BMMs. These results show that TEGO has the potential to be used as an anti-inflammatory agent.

Lobeglitazone inhibits LPS-induced NLRP3 inflammasome activation and inflammation in the liver

Liver inflammation is a common feature of chronic liver disease and is often associated with increased exposure of the liver to lipopolysaccharide (LPS). Kupffer cells (KCs) are macrophages in the liver and produce various cytokines. Activation of KCs through the NLRP3 inflammasome pathway leads to release of proinflammatory cytokines and induces hepatocyte injury and hepatic stellate cell (HSC) activation. Lobeglitazone is a peroxisome proliferator-activated receptor gamma ligand and a type of thiazolidinedione that elicits anti-inflammatory effects. However, there is no clear evidence that it has direct anti-inflammatory effects in the liver. This study showed that lobeglitazone reduces LPS-induced NLPR3 inflammasome activation and production of proinflammatory cytokines in primary KCs and hepatocytes. Cytokines secreted by activated KCs increased hepatocyte inflammation and HSC activation, and lobeglitazone inhibited these responses. In addition, lobeglitazone suppressed liver fibrosis by inhibiting LPS-induced transforming growth factor (TGF)-β secretion and TGF-β-induced CTGF expression. The inhibitory effect of lobeglitazone on inflammasome activation was associated with suppression of liver fibrosis. These results suggest that lobeglitazone may be a treatment option for inflammation and fibrosis in the liver.

Transplantation of neuron-inducing grafts embedding positively charged gold nanoparticles for the treatment of spinal cord injury

In this study, we aimed to investigate the recovery after traumatic spinal cord injury (SCI) by inducing cellular differentiation of transplanted neural stem cells (NSCs) into neurons. We dissociated NSCs from the spinal cords of Fisher 344 rat embryos. An injectable gel crosslinked with glycol chitosan and oxidized hyaluronate was used as a vehicle for NSC transplantation. The gel graft containing the NSC and positively charged gold nanoparticles (pGNP) was implanted into spinal cord lesions in Sprague-Dawley rats (NSC-pGNP gel group). Cellular differentiation of grafted NSCs into neurons (stained with β-tubulin III [also called Tuj1]) was significantly increased in the NSC-pGNP gel group (***p < 0.001) compared to those of two control groups (NSC and NSC gel groups) in the SCI conditions. The NSC-pGNP gel group showed the lowest differentiation into astrocytes (stained with glial fibrillary acidic protein). Regeneration of damaged axons (stained with biotinylated dextran amines) within the lesion was two-fold higher in the NSC-pGNP gel group than that in the NSC gel group. The highest locomotor scores were also found in the NSC-pGNP gel group. These outcomes suggest that neuron-inducing pGNP gel graft embedding embryonic spinal cord-derived NSCs can be a useful type of stem cell therapy after SCI.