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Background: Type 2 diabetes mellitus (T2DM) is becoming a major global health concern, especially in developing nations. The high prevalence of obesity and related diabetes cases are attributed to rapid economic progress, physical inactivity, the consumption of high-calorie foods, and changing lifestyles. Objectives: We investigated the roles of pro-inflammatory chemokines CCL1, 2, 4, and 5 in T2DM with varying levels of obesity in the Asir region of Saudi Arabia. Materials and Methods: In total, 170 confirmed T2DM subjects and a normal control group were enrolled. Demographic data, serum levels of CCL-1, 2, 4, and 5, and biochemical indices were assessed in the subjects and control groups by standard procedures. Results: T2DM subjects were divided into four groups: A (normal body weight), B (overweight), C (obese), and D (highly obese). We observed that male and female control subjects had similar mean serum concentrations of pro-inflammatory chemokines CCL-1, 2, 4, and 5. T2DM subjects in all the four groups showed significantly higher levels of all the four chemokines compared to the controls, regardless of gender. In T2DM subjects with obesity and severe obesity, the rise was most significant. There was a progressive rise in the concentrations of CCL-1, 2, and 4 in T2DM subjects with increasing BMI. Serum CCL5 levels increased significantly in all T2DM subject groups. The increase in CCL5 was more predominant in normal-weight people, compared to overweight and obese T2DM subjects. Conclusions: Male and female control subjects had similar serum levels of pro-inflammatory chemokines CCL-1, 2, 4, and 5. The progressive rise in blood concentrations of three pro-inflammatory chemokines CCL-1, 2, and 4 in T2DM subjects with increasing BMI supports the idea that dyslipidemia and obesity contribute to chronic inflammation and insulin resistance. Serum CCL5 levels increased significantly in all T2DM subject groups. The selective and more pronounced increase in CCL5 in the T2DM group with normal BMI, compared to subjects with varying degrees of obesity, was rather surprising. Further research is needed to determine if CCL5 underexpression in overweight and obese T2DM subjects is due to some unexplained counterbalancing processes. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) liver metastasis, albeit a stage‐IV disease, is completely curable by surgical resection in selected patients. In addressing the molecular basics of this phenomenon, differentially expressed genes at primary and liver metastatic sites were screened by RNA sequencing with the use of paraffin‐embedded surgical specimens. Chemokine C‐C motif ligand 1 (CCL1), a chemotactic factor for a ligand of the chemokine C‐C motif receptor 8 (CCR8), was isolated as one of the differentially expressed genes. Histological analysis revealed that the number of CCL1‐positive cells, mainly tumour associated macrophages (TAMs) located in the stroma of CRC, decreased significantly at liver metastatic sites, while the expression level of CCR8 on CRC remained unchanged. To explore the biological significance of the CCL1‐CCR8 axis in CRC, CCR8‐positive CRC cell line Colo320DM was used to assess the effect of the CCL1‐CCR8 axis on major signalling pathways, epithelial mesenchymal transition induction and cell motility. Upon stimulation of recombinant CCL1 (rCCL1), phosphorylation of AKT was observed in Colo320DM cells; on the other hand, the corresponding significant increase in MMP‐2 levels demonstrated by RT‐qPCR was nullified by siRNA (siCCR8). In the scratch test, rCCL1 treatment significantly increased the motility of Colo320DM cells, which was similarly nullified by siCCR8. Thus, the activation of the CCL1‐CCR8 axis is a positive regulator of CRC tumour progression. Reduced CCL1 expression of TAMs at liver metastatic sites may partly explain the unique slow tumour progression of CRC, thus providing for a grace period for radical resection of metastatic lesions. [ABSTRACT FROM AUTHOR]

Background: Diabetic neuropathic pain (DNP) is a serious complication for diabetic patients involving nervous system. MicroRNAs (miRNAs) are small-noncoding RNAs which are dysregulated in neuropathic pain, and might be critical molecules for pain treatment. Our previous study has shown miR-184-5p was significantly downregulated in DNP. Therefore, the mechanism of miR-184-5p in DNP was investigated in this study., Methods: A DNP model was established through streptozotocin (STZ). The pharmacological tools were injected intrathecally, and pain behavior was evaluated by paw withdrawal mechanical thresholds (PWMTs). Bioinformatics analysis, Dual-luciferase reporter assay and fluorescence-in-situ-hybridization (FISH) were used to seek and confirm the potential target genes of miR-184-5p. The expression of relative genes and proteins was analyzed by quantitative reverse transcriptase real-time PCR (qPCR) and western blotting., Results: MiR-184-5p expression was down-regulated in spinal dorsal on days 7 and 14 after STZ, while intrathecal administration of miR-184-5p agomir attenuates neuropathic pain induced by DNP and intrathecal miR-184-5p antagomir induces pain behaviors in naïve mice. Chemokine CC motif ligand 1 (CCL1) was found to be a potential target of miR-184-5p and the protein expression of CCL1 and the mRNA expression of CCR8 were up-regulated in spinal dorsal on days 7 and 14 after STZ. The luciferase reporter assay and FISH demonstrated that CCL1 is a direct target of miR-184-5p. MiR-184-5p overexpression attenuated the expression of CCL1/CCR8 in DNP; intrathecal miR-184-5p antagomir increased the expression of CCL1/CCR8 in spinal dorsal of naïve mice., Conclusion: This research illustrates that miR-184-5p alleviates DNP through the inhibition of CCL1/CCR8 signaling expression.