Sichuan Neo Life Stem Cell Biotech, Inc.

Diabetic retinopathy (DR) is a leading cause of vision loss, driven by hyperglycemia-induced human retinal microvascular endothelial cell (HRMEC) dysfunction, mitochondrial impairment, oxidative stress, inflammation, and aberrant angiogenesis. Circular RNAs (circRNAs) have emerged as critical regulators in various ocular pathologies, yet their contributions to DR remain unclear. This study identified and characterized hsa_circ_0099682, derived from the alpha motif domain-containing protein 1B (ANKS1B) gene, and investigated its role and molecular mechanism in high glucose (HG)-induced HRMEC injury.

Hsa_circ_0099682 was validated as a genuine circRNA through bioinformatic analyses (circPrism, circBank), RNase R digestion, actinomycin D treatment, and PCR with divergent/convergent primers. HG-exposed HRMECs were transfected with siRNAs targeting hsa_circ_0099682, miR-125b-5p inhibitors, or heterogeneous nuclear ribonucleoprotein U (HNRNPU) overexpression constructs. Mitochondrial function was assessed by reactive oxygen species (ROS) measurement and JC-1 staining for mitochondrial membrane potential. Inflammatory and oxidative stress markers (interleukin [IL]-6, IL-1β, superoxide dismutase [SOD], and malondialdehyde [MDA]) were quantified by enzyme-linked immunosorbent assay (ELISA) and commercial kits. Apoptosis and tube formation assays evaluated cell survival and angiogenic potential. Luciferase reporter and RNA immunoprecipitation assays confirmed ceRNA interactions. streptozotocin-induced DR rats were treated with AAV-shRNA to silence hsa_circ_0099682. Hematoxylin and eosin staining, immunofluorescence, ELISA, and Western blot analyses were performed to assess retinal structure, inflammation, oxidative stress, and angiogenic markers.

Hsa_circ_0099682 showed stable circular configuration and abundant cytoplasmic localization. In HG-stressed HRMECs, hsa_circ_0099682 knockdown reduced ROS accumulation, preserved mitochondrial membrane potential, diminished IL-6 and IL-1β secretion, enhanced antioxidant capacity, lowered apoptosis, and suppressed tube-forming ability. Mechanistically, hsa_circ_0099682 functioned as a sponge for miR-125b-5p, thereby relieving miR-125b-5p-mediated repression of HNRNPU. Inhibiting miR-125b-5p or overexpressing HNRNPU reversed the protective effects of hsa_circ_0099682 knockdown. In DR rats, silencing hsa_circ_0099682 improved retinal structural integrity, mitigated inflammation and oxidative stress, and restored balance in angiogenesis-related protein expression.

Hsa_circ_0099682 accelerates DR progression by suppressing miR-125b-5p, enhancing HNRNPU expression, and inducing mitochondrial dysfunction, inflammation, and irregular neoangiogenesis.

To analyze the relationship between the peripheral blood absolute lymphocyte count (ALC)/absolute monocyte count (AMC) ratio, soluble interleukin 2 receptor (sIL-2R) level, serum programmed cell death 1 (PD-1) level, and the prognosis of patients with diffuse large B-cell lymphoma (DLBCL).

A total of 78 patients with DLBCL admitted to hospital and 30 healthy controls were enrolled as the case group and control group between August 2019 and June 2020, respectively. The ALC/AMC ratio and the levels of sIL-2R and serum PD-1 between the 2 groups and among patients with different prognoses were compared. The evaluation efficiency of these 3 factors for the prognosis of DLBCL patients was analyzed by receiver operating characteristic (ROC) curves. The risk factors affecting the 1-year survival rate were analyzed by the Cox hazard model.

The levels of sIL-2R, AMC, and PD-1 in the case group were significantly higher than those in the control group, while the ALC/AMC ratio was lower than that in the control group (P<0.05). The levels of sIL-2R and PD-1 in the poor prognosis group were significantly higher than those in the good prognosis group, while the ALC/AMC ratio was lower than that in the good prognosis group (P<0.05). The areas under the ROC curve (AUCs) of sIL-2R level, serum PD-1 level, and the ALC/AMC ratio in evaluating the prognosis of DLBCL patients were 0.805 (95% CI: 0.700-0.886), 0.825 (95% CI: 0.722-0.902), 0.792 (95% CI: 0.685-0.876), respectively. The critical values were 474.80 µg/L, 206.85 pg/mL and 3.01, respectively. The differences in the 1-year survival rate among DLBCL patients with different tumor sizes, B symptoms, sIL-2R levels, and ALC/AMC ratios were statistically significant (P<0.05). B symptoms (RR =1.721) and ALC/AMC ratio lower than 3.01 (RR =1.484) were independent influencing factors of the 1-year survival rate in DLBCL patients (P<0.05).

The ALC/AMC ratio, sIL-2R level, and serum PD-1 level can effectively assess the prognosis of DLBCL patients. B symptoms and ALC/AMC ratio lower than 3.01 are risk factors affecting the 1-year survival rate of patients.

Diabetic nephropathy (DN) is one of the most severe chronic diabetic complications and the main cause of end-stage renal disease. Chronic inflammation plays a key role in the development of DN. However, few treatment strategies are available; therefore, new and effective strategies to ameliorate DN at the early stage must be identified.

Mesenchymal stem cells (MSCs) are characterized by anti-inflammatory and immune regulatory abilities. We developed a rhesus macaque model of DN and administered MSCs four times over 2 months. We measured blood glucose level, HbA1c, and levels of renal function parameters in the blood and urine, and cytokine levels in the kidney and blood circulatory system of rhesus macaques. Also, we analyzed the renal pathological changes of rhesus macaques. In vitro, we treated tubular epithelial cells (HK2) with 30 mmol/L glucose and 10 ng/mL human recombinant TNF-alpha (rhTNF-α) and explored the effects of MSCs on inflammation and Na+-glucose cotransporter 2 (SGLT2) expression in HK2.

We found that MSCs decreased the blood glucose level and daily insulin requirement of DN rhesus macaques. Furthermore, MSCs had a dominant function in improving renal function and decreasing SGLT2 expression on renal tubular epithelial cells. Also, renal pathological changes were ameliorated after MSC treatment. Moreover, MSCs powerfully reduced inflammation, especially decreased the level of pro-inflammatory cytokine interleukin-16 (IL-16), in the kidney and blood circulatory system.

Our study is an important step to explore the mechanism of MSCs in ameliorating the early stage of DN, potentially through influencing SGLT2 expression and resulting in improved glycemic control and anti-inflammation. We hope these findings would provide insights for the clinical application of MSCs in DN.