Pilocarpine improves submandibular gland dysfunction in irradiated rats by downregulating the tight junction protein claudin-4.

OBJECTIVES: To investigate the effects of radiation on paracellular pathway of rat submandibular glands (SMGs) and the mechanism of increasing secretion following treatment with pilocarpine. MATERIALS AND METHODS: In situ irradiation models of SMGs in Wistar rats were conducted, and the glands were exposed to X-radiation at a single dose of 20 Gy. Pilocarpine was intraperitoneally injected 60 min prior to radiation and continuous 6 days postirradiation for a total of 7 days. Salivary secretion, histological changes, pro-inflammatory cytokines, alterations in tight junctions (TJs), and functional membrane proteins aquaporin-5 (AQP5) and claudin-4 mediated by the muscarinic acetylcholine M3 subtype receptor were determined at 1 and 12 weeks after irradiation. RESULTS: Salivary secretion of the irradiated glands was reduced at 1 and 12 weeks. As well, acinar cell numbers, TJ width, and the levels of M3 receptor and AQP5 were decreased. In contrast, tumor necrosis factor-α, interleukin 6, interleukin 1α, and the expression of the TJ protein claudin-4 were significantly increased in irradiated SMGs. Notably, all the alterations were attenuated by pilocarpine treatment. CONCLUSIONS: Pilocarpine could improve the secretory function of irradiated rat SMGs via reducing inflammation, ameliorating the structural injury of TJs, and attenuating the up-regulation of claudin-4 expression.

Effect of ischemic preconditioning on radiation damage to the submandibular gland in rats.

To investigate the effects of radiation on rat submandibular glands and the possible protective effects of ischemic preconditioning, the submandibular glands of Wistar rats were subjected to in situ radiation after ischemic preconditioning. The glands were exposed to X-radiation at a single dose of 20 Gy. Ischemic preconditioning was achieved by three min of ischemia and three min of reperfusion, repeated three times before irradiation. Salivary secretion, histological changes, alterations in tight junctions, and the levels of oxidative stress, pro-inflammatory cytokines, and water secretion proteins mediated by the muscarinic acetylcholine M3 subtype receptor were determined at 1 and 12 weeks post-irradiation. In glands subjected to irradiation only, the secretion, superoxide dismutase activity, tight junction width, acinar cell number, and M3 receptor and aquaporin-5 levels were lower at 1 and 12 weeks than seen in the ischemically preconditioned irradiated glands. In contrast, tumor necrosis factor-α, malondialdehyde, myeloperoxidase activity, and the expression of the tight junction protein claudin-4 were significantly higher in the irradiated only glands. Our study revealed that radiation caused a series of injury-stress responses, especially damage to the water secretion pathway mediated by the M3 receptor that ultimately led to hyposecretion, which might play an important role in the dysfunction of the irradiated only glands. Ischemic preconditioning reduced the radiation-induced injury to submandibular glands and ameliorated salivary hyposecretion.

A new species of Syndicus (s. str.) Motschulsky (Coleoptera, Staphylinidae, Scydmaeninae) from East China.

Syndicus (s. str.) jaloszynskii Yin and Song, new species is described from Fujian and Zhejiang, East China. All material was collected in rotten woods. The habitus of both sexes, aedeagus, and spermatheca are illustrated. The new species can be readily separated from all known congeners by the strikingly large body size, the structure of aedeagal endophallus, and the form of spermatheca. This is the first species of the nominotypical subgenus of Syndicus known to occur in China.

Myrmecophilous rove beetles (Coleoptera: Staphylinidae) associated with Aenictus hodgsoni (Hymenoptera: Formicidae) from Thailand, with description of two new genera and three new species.

Three species of rove beetles (subfamily Aleocharinae) were collected from colonies of Aenictus hodgsoni Forel, 1901 in Khao Yai National Park, Thailand. They are classified into three genera, including two new genera, and described herein as: Aenictobia siamensis Maruyama, sp. n. (tribe Aenictoteratini), Aenictosymbia cornuta Maruyama, gen. & sp. n. (tribe Lomechusini) and Aenictoxenides mirabilis Maruyama, gen. & sp. n. (tribe Pygostenini). The systematic positions of the new genera are discussed.

Discoxenus Wasmann new to China with description of a new species (Coleoptera: Staphylinidae: Aleocharinae).

The termitophilous genus Discoxenus Wasmann, 1904 (Aleocharini: Compactopediina) is recorded from China for the first time and a new species from Guangdong is described under the name: Discoxenus shenzhenensis sp. nov.

Description of Sinometrius/ donggongensis/ sp. n. (Coleoptera, Carabidae, Paussinae) from the Donggong Mountains, East China.

Wrase and Schmidt (2006) established the genus Sinometrius Wrase Schmidt, 2006 to include the new species S. turnai Wrase Schmidt, 2006 from Hubei province, central China. They placed the new genus in the Paussine tribe Metriini, and compared it to the Nearctic genus Metrius Eschscholtz, 1829. Deuve (2020) described a second species S. jaroslavi Deuve, 2020 from Chongqing province.

Effect of stromal cell-derived factor-1/CXCR4 axis in neural stem cell transplantation for Parkinson's disease.

Previous studies have shown that neural stem cell transplantation has the potential to treat Parkinson's disease, but its specific mechanism of action is still unclear. Stromal cell-derived factor-1 and its receptor, chemokine receptor 4 (CXCR4), are important regulators of cell migration. We speculated that the CXCR4/stromal cell-derived factor 1 axis may be involved in the therapeutic effect of neural stem cell transplantation in the treatment of Parkinson's disease. A Parkinson's disease rat model was injected with 6-hydroxydopamine via the right ascending nigrostriatal dopaminergic pathway, and then treated with 5 µL of neural stem cell suspension (1.5 × 104/L) in the right substantia nigra. Rats were intraperitoneally injected once daily for 3 days with 1.25 mL/kg of the CXCR4 antagonist AMD3100 to observe changes after neural stem cell transplantation. Parkinson-like behavior in rats was detected using apomorphine-induced rotation. Immunofluorescence staining was used to determine the immunoreactivity of tyrosine hydroxylase, CXCR4, and stromal cell-derived factor-1 in the brain. Using quantitative real-time polymerase chain reaction, the mRNA expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra were measured. In addition, western blot assays were performed to analyze the protein expression of stromal cell-derived factor-1 and CXCR4. Our results demonstrated that neural stem cell transplantation noticeably reduced apomorphine-induced rotation, increased the mRNA and protein expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra, and enhanced the immunoreactivity of tyrosine hydroxylase, CXCR4, and stromal cell-derived factor-1 in the brain. Injection of AMD3100 inhibited the aforementioned effects. These findings suggest that the stromal cell-derived factor-1/CXCR4 axis may play a significant role in the therapeutic effect of neural stem cell transplantation in a rat model of Parkinson's disease. This study was approved by the Animal Care and Use Committee of Kunming Medical University, China (approval No. SYXKK2015-0002) on April 1, 2014.

Transplantation of Nurr1-overexpressing neural stem cells and microglia for treating parkinsonian rats.

BACKGROUND: Neural stem cells (NSCs) transplantation is considered a promising treatment for Parkinson's disease. But most NSCs are differentiated into glial cells rather than neurons, and only a few of them survive after transplantation due to the inflammatory environment. METHODS: In this study, neural stem cells (NSCs) and microglial cells both forced with the Nurr1 gene were transplanted into the striatum of the rat model of PD. The results were evaluated through reverse transcription polymerase chain reaction (RT-PCR), Western blot, and immunofluorescence analysis. RESULTS: The behavioral abnormalities of PD rats were improved by combined transplantation of NSCs and microglia, both forced with Nurr1. The number of tyrosine hydroxylase+ cells in the striatum of PD rats increased, and the number of Iba1+ cells decreased compared with the other groups. Moreover, the dopamine neurons differentiated from grafted NSCs could still be detected in the striatum of PD rats after 5 months. CONCLUSIONS: The results suggested that transplantation of Nurr1-overexpressing NSCs and microglia could improve the inhospitable host brain environments, which will be  a new potential strategy for the cell replacement therapy in PD.

First record of tribe Laenini (Coleoptera, Tenebrionidae, Lagriinae) from Shanghai, with description of a new species of the genus Laena Dejean.

Laena hongqiao sp. n. is described from Shanghai. This discovery expands the provincial distribution of the huge tenebrionid genus Laena in mainland China, and enriches the knowledge of the species diversity in Shanghai. A key modified from Schawaller 2008 and Wei Ren 2018 is provided to include this new species.

Flanged Bombardier beetles from Shanghai, China, with description of a new species in the genus Eustra Schmidt-Goebel (Coleoptera, Carabidae, Paussinae).

Four paussine species belonging to three different genera are discovered in Shanghai. A new species, Eustra shanghaiensis Song, sp. n., is described, illustrated, and distinguished from the treated congeners. New distributional data or biological notes on Eustra chinensis Bänninger, 1949, Itamus castaneus Schmidt-Goebel, 1846, and Platyrhopalus davidis Fairmaire, 1886 are provided.

Nurr1 promotes neurogenesis of dopaminergic neuron and represses inflammatory factors in the transwell coculture system of neural stem cells and microglia.

INTRODUCTION: Neural stem cells (NSCs) are the most promising cells for cell replacement therapy for Parkinson's disease (PD). However, a majority of the transplanted NSCs differentiated into glial cells, thereby limiting the clinical application. Previous studies indicated that chronic neuroinflammation plays a vital role in the degeneration of midbrain DA (mDA) neurons, which suggested the developing potential of therapies for PD by targeting the inflammatory processes. Thus, Nurr1 (nuclear receptor-related factor 1), a transcription factor, has been referred to play a pivotal role in both the differentiation of dopaminergic neurons in embryonic stages and the maintenance of the dopaminergic phenotype throughout life. AIM: This study investigated the effect of Nurr1 on neuroinflammation and differentiation of NSCs cocultured with primary microglia in the transwell coculture system. RESULTS: The results showed that Nurr1 exerted anti-inflammatory effects and promoted the differentiation of NSCs into dopaminergic neurons. CONCLUSIONS: The results suggested that Nurr1 protects dopaminergic neurons from neuroinflammation insults by limiting the production of neurotoxic mediators by microglia and maintain the survival of transplanted NSCs. These phenomena provided a new theoretical and experimental foundation for the transplantation of Nurr1-overexpressed NSCs as a potential treatment of PD.

Discovery of the genus Lebioderus (Coleoptera, Carabidae, Paussinae) from China, with description of two new species.

The rare paussine genus Lebioderus Westwood, 1838 is reported from China for the first time, based on two new species, L. sinicus Song & Maruyama sp. nov. and L. maolanus Song & Maruyama sp. nov. The type series of L. sinicus was collected from nests of Carebara Westwood, 1840 ants, which is also a first host record for Lebioderus.

Comparison of different stimulation parameters of repetitive transcranial magnetic stimulation for unilateral spatial neglect in stroke patients.

OBJECTIVE: In this study three different stimulation parameters of repetitive transcranial magnetic stimulation (rTMS) were tested to compare the efficacy of continuous theta burst stimulation (continuous TBS) for rehabilitation of unilateral spatial neglect (USN) in stroke patients. METHODS: Carefully selected cohort of thirty-eight stroke patients were randomly assigned to three treatment groups (1 Hz group, 10 Hz group and continuous TBS group) and sham group. Intervention in patients in the treatment group consisted of rTMS, while patients in the sham group received pseudo-stimulation for two weeks. All patients were administered star cancellation and line bisection tests at 4 different time points of the study. Further, all study subjects in the three treatment groups and sham group underwent diffusion-tensor imaging (DTI) at the beginning and at the end of treatment to calculate fractional anisotropy (FA) and mean diffusivity (MD). RESULTS: Among the three stimulation parameters, star cancellation and line bisection tests revealed significant differences in outcomes at the end of treatments and one month after the end of treatments, compared to beginning of the treatments. Importantly, continuous TBS group patients displayed the best curative effect, based on behavioral scoring, at one month after end of the treatments, followed by the 1Hz group and 10 Hz group. DTI results showed a significant increase in FA and MD in superior longitudinal fasciculus, superior occipitofrontal fascicle and inferior fronto-occipital fasciculus on the left side, as well as the capsula external and inferior fronto-occipital fasciculus on the right side, in patients after continuous TBS. In addition, compared to the sham group, patients stimulated with continuous TBS exhibited a dramatic increase in FA in the left external capsule. CONCLUSION: Our study presents strong evidence that rTMS significantly improves neurocognitive functions in USN, with continuous TBS showing the best curative effect. Enhanced connections in the white matter tract network related to visual attention, as assessed by DTI, might be the potential mechanism for the observed recovery in USN using continuous TBS.

Neuregulin-1 protects against acute optic nerve injury in rat model.

OBJECTIVES: In this study, we employed a rat model and examined the expression pattern of neuregulin-1 (NRG-1) in optic nerve and retinal ganglion cells (RGCs) in response to optic nerve injury to understand the role of NRG-1 in conferring protection against acute optic nerve injury. METHOD: Forty-eight male rats were randomly divided into two groups, the sham-operation group (n=24) and optic nerve injury group (n=24). Flash visual evoked potentials (FVEP) and fundography images were acquired at different time points following optic nerve injury (2h, 1d, 2d, 7d, 14d and 28d). Semi-quantitative analysis of NGR-1 expression pattern was performed by immunohistochemistry (IHC) staining. In a related experiment, 100 male rats were randomly divided into NGR-1 treatment group (n=60) (treated with increasing dose of NGR-1 at 0.5µg, 1µg and 3µg), normal saline (NS) group (n=20) and negative control group (n=20). Optic nerve injury was induced in all the animals and in situ cell death was measured by detecting the apoptosis rates using TUNEL assay. RESULTS: Fundus photography results revealed no detectable differences between the sham-operation group and optic nerve injury group at 2h, 1d, 2d and 7d. However at 2weeks, the optic discs turned pale in all animals in the optic nerve injury group. NRG-1 expression increased significantly at all time points in the optic nerve injury group (P<0.05), compared to the sham-operation group, with NRG-1 expression peaking at 14d and gradually declining by 28d. Statistically significant differences in amplitude and latency of P100 wave were also detected between the optic nerve injury and sham-operation group (P<0.05). In related experiment, compared to NS group, treatment with 1µg and 3µg of recombinant human NRG-1 resulted in statistically significant FVEP-P100 amplitude values (all P<0.05). Further, compared to the NS group, ganglion cell apoptosis was dramatically reduced in the NRG-1 group at all time points and the reduction was statistically significant in 3µg NRG-1 treatment group at 7d, 14d and 28d (all P<0.05). CONCLUSION: Our results strongly suggest that NRG-1 is highly effective in preserving normal optic nerve function and is essential for tissue repair following optic nerve injury. Thus, NRG-1 expression confers protection against acute optic nerve injury in a dose-dependent manner.

Three new species of the myrmecophilous genus Doryloxenus from China (Coleoptera, Staphylinidae, Aleocharinae).

Three new species of the pygostenine genus Doryloxenus Wasmann, viz., Doryloxenusaenictophilus sp. n. (from Zhejiang), Doryloxenustangliangi sp. n. (from Zhejiang), and Doryloxenussongzhigaoi sp. n. (from Yunnan), are described, illustrated and distinguished from the Asian congeners. An identification key to the Chinese species is given.

Descriptions of three new species of the Termitophilous tribe Termitopaediini in China (Coleoptera, Staphylinidae, Aleocharinae).

Three new species belonging to two genera of the aleocharine tribe Termitopaediini Seevers, viz., Dioxeuta rara Song & Li, sp. n., D. yunnanensis Song & Li, sp. n., and Termitopulex sinensis Song & Li, sp. n. from Baihualing Natural Reserve (Southwest China: Yunnan) are described and illustrated. This is the first record of Termitopulex Fauvel, 1899 from China.

Description of Pella maoershanensis sp. n. (Coleoptera, Staphylinidae, Aleocharinae) associated with Lasius spathepus from Guangxi, South China.

Pellamaoershanensis Song & Li, sp. n., collected from a colony of Lasius (Dendrolasius) spathepus in Maoershan Natural Reserve, Guangxi, is diagnosed, described and illustrated. The discovery represents the first record of the genus in South China.

The larva of Eustra (Coleoptera, Paussinae, Ozaenini):a facultative associate of ants.

Larvae of the ground beetle genus Eustra Schmidt-Goebel are described and illustrated for the first time and some biological notes are reported. One specimen of an unknown Eustra species was collected while excavating a nest of the ant Pachycondyla javana Mayr, in Taiwan, which is the first report of a paussine associated with a member of the ant subfamily Ponerinae. Several larvae and adults of a second species, Eustra chinensis Bänninger, were collected in Shanghai under bark with no association with ants. First instar larvae of the latter species were also reared in the lab. The occurrence of larvae of the genus Eustra both inside and outside ant nests, together with a report of adults collected inside a nest in Taiwan, suggests that members of this genus may be facultative predators or facultative symbionts of ants, an attribute that has never been reported for this genus. The larvae of Eustra show several unique features, including a peculiar bidentate mandibular apex, an extremely long galea, one of two tarsal claws greatly reduced, abdominal setae (including those of terminal disk) elongate and clavate at apex, urogomphi wide and flattened, and inflated sensilla S-I. Larvae were studied by both optical and scanning electron microscopy, their morphological features are compared with those of other described Paussinae larvae, and their potential phylogenetic and functional significance are discussed.

Transplantation of hypoxia preconditioned bone marrow mesenchymal stem cells improves survival of ultra-long random skin flap.

BACKGROUND: Random flap is one kind of the most widely used skin flaps in reconstructive surgery; however, partial necrosis of its distal end remains a significant problem now. The aim of this study was to evaluate the effect of hypoxia preconditioned bone marrow mesenchymal stem cells (HpBMSCs) transplantation on ultra-long random skin flap survival in rats. METHODS: Normoxic bone marrow mesenchymal stem cells (nBMSCs) were cultured under normoxia (20% O2) and HpBMSCs under hypoxia (1% O2) for 48 hours before transplantation. Thirty Sprague-Dawley rats were randomly divided into control group, nBMSCs group and HpBMSCs group with each consisting of 10 rats. Survival area of ultra-long random skin flap on the dorsal of rats was measured seven days after flap surgery and cell transplantation. Cell survival in vivo, microvessel density and vascular endothelial growth factor (VEGF) were evaluated by histological examination and enzyme-linked immunosorbent assay. RESULTS: Compared with other two groups, flap survival area in HpBMSCs group was significantly larger (P < 0.05). Microvessel density in HpBMSCs group (36.20 ± 8.19) was higher than that in nBMSCs group (30.01 ± 5.68) and control group (17.60 ± 4.19) (P < 0.05). VEGF in HpBMSCs group ((300.05 ± 50.41) pg/g) was higher than those in nBMSCs group ((240.55 ± 33.64) pg/g) and control group ((191.65 ± 32.58) pg/g) (P < 0.05). CONCLUSION: HpBMSCs transplantation improves ultra-long random skin flap survival via promoting angiogenesis of more survival cells.