MSC-Derived Small Extracellular Vesicles Attenuate Autoimmune Dacryoadenitis by Promoting M2 Macrophage Polarization and Inducing Tregs via miR-100-5p.

Background: Mesenchymal stem cell-derived small extracellular vesicles (MSC-sEVs) have been increasingly proved as promising immunomodulators against some autoimmune disorders. However, the possible effect and the underlying mechanism of MSC-sEVs in autoimmune dry eye have been rarely studied. Methods: Small extracellular vesicles from human umbilical cord mesenchymal stem cells (hUC-MSC-sEVs) were subconjunctivally injected to rabbit dry eye model, and their preventive or therapeutical effects were assessed by recording the clinical and histological scores. Quantitative real-time PCR (Q-PCR), western blot and flow cytometry were performed to evaluate the immunomodulatory effects of hUC-MSC-sEVs on macrophages and T regulatory cells (Tregs) both in vivo and in vitro, and the in vitro T cell proliferation was detected by Bromodeoxyuridine (BrdU) assay. In addition, high expression of miR-100-5p in hUC-MSC-sEVs was identified by Q-PCR, and the functional role of sEVs-miR-100-5p on macrophages was explored by a series of co-culture experiments using sEVs derived from hUC-MSCs transfected with miR-100-5p inhibitor. Results: We firstly demonstrated that hUC-MSC-sEVs had the preventive and therapeutical effects on rabbit autoimmune dacryoadenitis, an animal model of Sjögren's syndrome (SS) dry eye. Further investigation revealed that hUC-MSC-sEVs administration effectively elicited macrophages into an anti-inflammatory M2 phenotype and elevated the proportion of Tregs both in vivo and in vitro, which contributed to reduced inflammation and improved tissue damage. Importantly, hUC-MSC-sEVs-educated macrophages with M2-like phenotype exhibited strong capacity to inhibit CD4+ T cell proliferation and promote Treg generation in vitro. Mechanistically, miR-100-5p was highly enriched in hUC-MSC-sEVs, and knockdown of miR-100-5p in hUC-MSC-sEVs partially blunted the promotion of hUC-MSC-sEVs on M2 macrophage polarization and even attenuated the effect of hUC-MSC-sEVs-educated macrophages on T cell suppression and Treg expansion. Conclusion: Our data indicated that hUC-MSC-sEVs alleviated autoimmune dacryoadenitis by promoting M2 macrophage polarization and Treg generation possibly through shuttling miR-100-5p. This study sheds new light on the application of MSC-sEVs as a promising therapeutic method for SS dry eye.

Protective Effect and Mechanism of Bone Morphogenetic Protein-4 on Apoptosis of Human Lens Epithelium Cells under Oxidative Stress.

Bone morphogenetic proteins (BMPs), a member of the transforming growth factor ß (TGF-ß) superfamily, are abundant in human ocular tissues and play an important role in lens development. Targeted deletion of BMP-4 in mice results in failure of lens placode formation. Following lens maturation, the formation of senile cataracts is demonstrably associated with free radical-related oxidative stress. Previous studies reported that BMPs play an antiapoptotic role in cells under oxidative stress, and the BMP-4 signal is important in inflammation regulation and homeostasis. BMP-4 evidently suppressed the apoptosis of human lens epithelial cells (HLECS) under oxidative stress induced by H2O2. This protective antiapoptotic effect is partly due to a decrease in caspase-3 activity and reactive oxygen species (ROS) level. Furthermore, the expression of activating transcription factor- (ATF-) 6 and Krüppel-like factor- (KLF-) 6 increased under oxidative stress and decreased after BMP-4 treatment.

Effect of chidamide on treating hepatosplenic T-cell lymphoma: A case report.

BACKGROUND: Hepatosplenic T-cell lymphoma (HSTCL) is a rare subtype of non-Hodgkin's lymphoma, which has an aggressive clinical course and an extremely poor prognosis. Chidamide is a novel, orally active, benzamide-type histone deacetylase (HDAC) inhibitor that has been used for peripheral T-cell lymphoma (PTCL) treatment. However, to date, there has been no report of the treatment and effect of the HDAC inhibitor chidamide in HSTCL, which is a special subtype of PTCL. CASE SUMMARY: A 45-year-old male patient was admitted with splenomegaly and slight bicytopenia. He was diagnosed with HSTCL via splenectomy. The patient was treated with fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with high-dose methotrexate and cytarabine regiment as inductive therapy. Unfortunately, the disease progressed rapidly during chemotherapy before a suitable allogeneic gene transplant donor was found. The chidamide-combined chemotherapy regimen and single-drug oral maintenance regimen achieved complete remission, duration of response of 9 mo, and overall survival of 15 mo. CONCLUSION: The novel agent chidamide can be used in HSTCL to achieve deep remission and improve the duration of response and overall survival.

Tetramethylpyrazine ameliorated disuse-induced gastrocnemius muscle atrophy in hindlimb unloading rats through suppression of Ca2+/ROS-mediated apoptosis.

The purpose of this study was to examine the possible mechanism underlying the protective effect of tetramethylpyrazine (TMP) against disuse-induced muscle atrophy. Sprague-Dawley rats were randomly assigned to receive 14 days of hindlimb unloading (HLU, a model of disuse atrophy) or cage controls. The rats were given TMP (60 mg/kg body mass) or vehicle (water) by gavage. Compared with vehicle treatment, TMP significantly attenuated the loss of gastrocnemius muscle mass (-33.56%, P < 0.01), the decrease of cross-sectional area of slow fiber (-10.99%, P < 0.05) and fast fiber (-15.78%, P < 0.01) during HLU. Although TMP failed to further improve recovery of muscle function or fatigability compared with vehicle treatment, it can suppress the higher level of lactate (-22.71%, P < 0.01) induced by HLU. Besides, TMP could effectually reduce the increased protein expression of muscle RING-finger protein 1 induced by HLU (-14.52%, P < 0.01). Furthermore, TMP can ameliorate the calcium overload (-54.39%, P < 0.05), the increase of malondialdehyde content (-19.82%, P < 0.05), the decrease of superoxide dismutase activity (21.34%, P < 0.05), and myonuclear apoptosis (-78.22%, P < 0.01) induced by HLU. Moreover, TMP significantly reduced HLU-induced increase of Bax to B-cell lymphoma 2 (-36.36%, P < 0.01) and cytochrome c release (-36.16%, P < 0.05). In conclusion, TMP attenuated HLU-induced gastrocnemius muscle atrophy through suppression of Ca2+/reactive oxygen species increase and consequent proteolysis and apoptosis. Therefore, TMP might exhibit therapeutic effect against oxidative stress, cytosolic calcium overload, and mitochondrial damage in disuse-induced muscle atrophy.

Remarkable preservation of Ca(2+) homeostasis and inhibition of apoptosis contribute to anti-muscle atrophy effect in hibernating Daurian ground squirrels.

The underlying mechanisms that hibernators deviated from muscle atrophy during prolonged hibernating inactivity remain elusive. This study tested the hypothesis that the maintenance of intracellular Ca(2+) homeostasis and inhibition of apoptosis would be responsible for preventing muscle atrophy in hibernating Daurian ground squirrels. The results showed that intracellular Ca(2+) homeostasis was maintained in soleus and extensor digitorum longus (EDL) in hibernation and post-hibernation, while cytosolic Ca(2+) was overloaded in gastrocnemius (GAS) in hibernation with a recovery in post-hibernation. The Ca(2+) overload was also observed in interbout arousals in all three type muscles. Besides, the Bax/Bcl-2 ratio was unchanged in transcriptional level among pre-hibernation, hibernation and interbout arousals, and reduced to a minimum in post-hibernation. Furthermore, the Bax/Bcl-2 ratio in protein level was reduced in hibernation but recovered in interbout arousals. Although cytochrome C was increased in GAS and EDL in post-hibernation, no apoptosis was observed by TUNEL assay. These findings suggested that the intracellular Ca(2+) homeostasis in hibernation might be regulated by the cytosolic Ca(2+) overload during interbout arousals, which were likely responsible for preventing muscle atrophy via inhibition of apoptosis. Moreover, the muscle-specificity indicated that the different mechanisms against disuse-induced atrophy might be involved in different muscles in hibernation.

Overexpressing MhNPR1 in transgenic Fuji apples enhances resistance to apple powdery mildew.

Fuji is susceptible to fungal diseases like apple powdery mildew. Non-expressor of pathogenesis-related gene 1 (NPR1) plays a key role in regulating salicylic acid (SA)-mediated systemic acquired resistance (SAR). Previous studies show that overexpressing the Malus hupehensis-derived NPR1 (MhNPR1) gene in tobacco induces the transcript expression of pathogenesis-related genes (PRs) and resistance to the fungus Botrytis cinerea. In this study we introduced the MhNPR1 gene into the 'Fuji' apple via Agrobacterium-mediated transformation. Four transgenic apple lines were verified by PCR and RT-PCR. The semi-quantitative RT-PCR results showed that transcript overexpression of the MhNPR1 gene induced the expression of MdPRs and MdMLO genes known to interact with powdery mildew. Furthermore, the transgenic apple plants resisted infection by apple powdery mildew better than the wild-type plants. As a result, transcript overexpression of the MhNPR1 gene induced SAR and enhanced the Fuji apple's resistance to fungal disease.

[Characters of multifocal electroretinogram in different grades of diabetic macular edema].

OBJECTIVE: To investigate the characters of multifocal electroretinogram (mfERG) in different grades of diabetic macular edema defined by optical coherence tomography (OCT). METHODS: MfERG and OCT were performed in 57 eyes of diabetic macular edema (DME) patients and 35 eyes of the control group. According to the macular thickness measured by OCT, eyes with DME were divided into three groups: mild, moderate and severe DMEs. RESULTS: In mild DME, the response densities of N(1) were attenuated in ring 4[(14.67 ± 4.91) nV×deg(-2)] to ring 5 [(11.65 ± 3.89) nV×deg(-2)] respectively (t = 2.179, 2.529; P < 0.05). The latencies of P(1) was prolonged significantly in ring 3 [(40.61 ± 4.10) ms] (t = -2.133, P < 0.05). In moderate DME, the response densities of P(1) and N(1) were attenuated in ring 1 [(149.50 ± 29.01) nV×deg(-2)], ring 2 [(59.33 ± 25.96) nV×deg(-2)], ring 3 [(41.83 ± 9.78) nV×deg(-2)], and ring 5 [(22.00 ± 5.52) nV×deg(-2)] respectively (t = 3.610, 2.168, 2.627, 3.445; P < 0.05). The latencies of P(1) and N(1) were prolonged significantly in ring 3 [(42.86 ± 4.72) ms], ring 4 [(44.33 ± 5.56) ms], ring 5 [(46.31 ± 4.72) ms] (t = -3.150, -3.210, -3.968; P < 0.05) and ring 3 [(23.05 ± 3.06) ms], ring 4 [(22.41 ± 3.36) ms] (t = -2.845, -2.098; P < 0.05) respectively. In severe DME. The response densities of P(1) and N(1) were attenuated in ring 1 [(110.00 ± 20.68) nV×deg(-2)], ring 2 [(62.40 ± 27.90) nV×deg(-2)], ring 3[(39.20 ± 19.65) nV×deg(-2)], ring 5 [(21.60 ± 11.12) nV×deg(-2)] (t = 7.135, 1.782, 2.214, 2.609; P < 0.05) and ring 1 [(41.63 ± 39.17) nV×deg(-2)], ring 3 [(16.63 ± 5.81) nV×deg(-2)], ring 4 [(11.20 ± 7.42) nV×deg(-2)], ring 5 [(9.05 ± 4.63) nV×deg(-2)] (t = 2.714, 2.282, 2.736, 2.858; P < 0.05) respectively. The latencies of P(1) and N(1) were prolonged significantly in ring 1 [(35.12 ± 8.44) ms], ring 3 [(40.44 ± 2.10) ms], ring 4 [(42.80 ± 3.74) ms] (t = 3.426, -2.710, -3.120; P < 0.05) and ring 4 [(23.36 ± 4.05) ms] (t = -2.572; P < 0.05) respectively. CONCLUSION: As the progress of DME, the thickness of macular fovea had significant correlation with responses of multifocal electroretinogram in patients with moderate or severe DME. MfERG combined with OCT can evaluate the changes of morphology and local retinal function in macula area objectively and quantitatively.