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Background: Parkinson's disease (PD) is the second most common neurodegenerative disease featured to mitochondrial dysfunction in neuronal cells. Dynamin-related protein 1 (Drp1) is an important regulator of mitochondrial fission and subsequent mitophagy. Mangiferin (MGF) is a glucosyl xanthone mainly derived from Mangifera indica L., possessing multifaceted properties, e.g., antioxidant, anti-inflammatory, and enhancement of cognitive ability. Besides, it can cross the blood-brain barrier, thereby exerting a neuroprotective effect. However, so far, MGF's effect in balancing mitochondrial homeostasis via regulation of Drp1 level and mitophagic pathway in PD remains rarely reported.Purpose: We aimed to investigate the neuroprotective effect of MGF against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD and examine the possible mechanisms.Methods: We utilized C57BL/6 mice exposed to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP); Behavioral parameters, containing the open field test, balance beam, pole test, and rotarod test, assessed the locomotor activity; immunohistochemistry assessed the number of TH-positive neurons; transmission electron microscopy detected ultrastructural mitochondrial morphology in the dopaminergic neuron; complex I enzymatic activity microplate assay kit measured the mitochondrial complex I activity; ATP determination kit measured ATP levels in mitochondria isolated from cells or striatal tissues; western blot measured the levels of Drp1 and mitophagic proteins.Results: We observed that MGF could mitigate motor deficiency and improve the expression of tyrosine hydroxylase in the substantia nigra of MPTP-induced PD mice. Furthermore, MGF not only ameliorated mitochondrial ultrastructure, but also improved mitochondrial ATP content. Within mitochondria, MGF could reduce Drp1 expression and reverse the expressions of mitophagic proteins, including PINK1, Parkin, NIX, BNIP3, FUNDC1, and p62.Conclusion: Present study indicates that MGF benefits mitochondrial networks by recovering mitochondrial ultrastructure and ATP contents, reducing mitochondrial Drp1, and modulating mitophagic proteins in the MPTP-induced PD mice model, which revealed a novel acting mechanism of MGF in PD's treatment. [ABSTRACT FROM AUTHOR]

Abstract: The stratigraphy, age, depositional environment and correlation of the collision-related variegated sandstone and conglomerate beds exposed along the southern side of the Gangdise Mountains to the north of the Yarlung Zangbo suture in the Xigaze region, Xizang (Tibet) have been much debated. Generally referred to as the Dagzhuka Formation, these beds of great thickness have, until recently, not been reported to contain any convincing fossils. Two distinctly different palynological assemblages, indicating Late Cretaceous and Oligocene–Early Miocene ages respectively, have now been recovered from lithologically distinguishable units of the sedimentary succession at Qiabulin to the west of the town of Xigaze. This means that instead of one stratigraphic unit, as has been generally accepted hitherto, at least two are represented. As a result, the Dagzhuga Formation is considered here to refer only to the Cenozoic deposits and the Qiabulin Formation, previously regarded as a synonym, is resurrected to accommodate the Cretaceous beds. These two formations were juxtaposed by tectonic movements. Our finding indicates that the stratigraphic successions on the southern Laurasian continental margin of Xizang reflect changes from a deep forearc basin through shallow littoral environments to a mountainous landscape during the Late Cretaceous and early Cenozoic. This interpretation compares well with those documented from the Gamba and Tingri districts to the south of the Yarlung Zangbo suture. [Copyright &y& Elsevier]

Highlights • DJ-1 knockdown resulted in mitochondrial dysfunction. • loss of DJ-1 suppressed Akt pathway, and reduced nuclear translocation of Nrf2. • DJ-1 deficiency led to an obvious increase in the ROS level, and then activated JNK signaling. Abstract Deletions or some mutations in the gene encoding the multifunctional protein, DJ-1, have been considered to be linked with autosomal recessive early onset Parkinson's disease (PD). Current emerging evidence suggests that DJ-1 is involved in the protection against oxidative stress-induced mitochondrial damage. However, the exact molecular mechanisms underlying this are not completely clear. The aim of this study was to investigate the effects of DJ-1 on the Akt pathway, nuclear factor erythroid 2-related factor (Nrf2), and c-Jun N-terminal kinase (JNK) with regard to modulating mitochondrial function. Here we showed that knockdown of DJ-1 resulted in mitochondrial dysfunction, including a decrease in active mitochondrial mass, complex I deficits, and inhibition of cellular adenosine 5′-triphosphate (ATP) content in the dopaminergic neuron-like cells PC12 and SH-SY5Y. Additionally, loss of DJ-1 impaired Akt signaling, and reduced nuclear translocation of Nrf2, thereby inhibiting activity of Nrf2-regulated downstream antioxidant enzymes such as heme oxygenase-1 and NAD(P)H quinone oxidoreductase 1. Moreover, DJ-1 knockdown also led to a significant increase in the mitochondrial reactive oxygen species, and then promoted the activation of JNK pathways. Furthermore, oxidative stress and mitochondrial dysfunction induced by knockdown of DJ-1 were blocked by a JNK inhibitor, which confirmed the important role of JNK activation in mitochondrial dysfunction. In conclusion, the present study indicates that DJ-1 knockdown leads to mitochondrial dysfunction in dopaminergic neuron-like cells, at least in part, through suppressing the Akt/GSK3β pathway and impairing the oxidative stress response, as well as through the subsequent increased JNK activation in dopaminergic neuron-like cells. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Da-Bu-Yin-Wan (DBYW), a historically traditional Chinese medicine formula, was originally defined over 600 years ago. In recent decades, DBYW was clinically employed to treat Parkinson's disease (PD). Aim of the study To explore the underlying mechanism of DBYW on mitochondrial function, we investigated the effect of DBYW on mitochondrial function from the perspectives of DJ-1 and Akt signaling. Materials and methods Human derived neuroblastoma SH-SY5Y cells were transiently transfected with the plasmid pcDNA3-Flag-DJ-1 aimed to overexpress the DJ-1 protein. Transfected cells were treated with 1-methyl-4-phenylpyridinium (MPP + ), a PD-related mitochondrial complex I inhibitor, in the absence and presence of DBYW. The cell viability was assessed by Cell Counting Kit-8 assay. The protein expressions of DJ-1 and Akt signaling were examined by western blotting. The mitochondrial mass was evaluated by confocal fluorescence microscopy. The mitochondrial complex I activity and cellular ATP content were measured by commercial kits. Results Transfection with pcDNA3-Flag-DJ-1 decreased the MPP + -induced toxicity and overexpressed the DJ-1. In DJ-1 overexpressed cells, the mitochondrial mass was raised, mitochondrial complex I activity was improved, and cellular ATP content was increased. In addition, overexpression of DJ-1 augmented the Akt phosphorylation on threonine 308 and serine 473. Moreover, DBYW promoted the above effects in DJ-1 expressed cells. Conclusions These data suggest that DJ-1 protects the mitochondrial function by medicating Akt phosphorylation in MPP + -treated SH-SY5Y cells. Moreover, DBYW enhances the protective effect of DJ-1 medicated Akt phosphorylation on mitochondrial function. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Da-Bu-Yin-Wan (DBYW) and Qian-Zheng-San (QZS), two traditional Chinese herbal formulas, were clinically employed to treat Parkinson''s disease (PD) for decades. Aim of the study: Our previous studies demonstrated neuroprotective effects of DBYW and QZS on mitochondrial function in mice model of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). In present research, we aimed to investigate the possible neuroprotective mechanisms of DBYW and QZS. Materials and methods: The effects of DBYW and QZS on the behavioral changes (pole test), expression of tyrosine hydroxylase (TH) of substantia nigra by immunohistochemistry, monoaminergic contents and activity of striatum by high performance liquid chromatography, neuronal ultrastructure changes by transmission electron microscopy, mitochondrial DNA (mtDNA) damage by long-extension polymerase chain reaction (PCR), and mRNA expression of mitochondrial subunit NADH dehydrogenase 1(ND1) by qualitative real-time PCR were investigated. Results: Present study demonstrated that DBYW and QZS not only ameliorated the behavior induced by the administration of MPTP and synergistically prevented the decreasing of TH expression, but also increased monoaminergic contents and activity, improved the ultrastructural changes, decreased the mtDNA damage, and synergistically up-regulated the expression of ND1 in mRNA level. Conclusions: These results suggest that DBYW and QZS possess anti-parkinsonism and neuroprotective properties. [Copyright &y& Elsevier]

Parkinson's disease (PD) is the prevalent neurodegenerative disorder characterized by the degeneration of the nigrostriatal neurons. Dynamin-related protein 1 (Drp1) is a key regulator mediating mitochondrial fission and affecting mitophagy in neurons. It has been reported that the inhibition of Drp1 may be beneficial to PD. However, the role of Drp1 and mitophagy in PD remains elusive. Therefore, in this research, we investigated the role of Drp1 and the underlying mechanisms in the mice model of PD. We used the dynasore, a GTPase inhibitor, to inhibit the expression of Drp1. We found that inhibition of Drp1 could ameliorate the motor deficits and the expression of tyrosine hydroxylase in the mice of the PD model. But Drp1 inhibition did not affect mitochondria number and morphological parameters. Moreover, suppression of Drp1 up-regulated the mitochondrial expressions of PINK1 and Parkin while not affected the expressions of NIX and BNIP3. Conclusively, our findings suggest that the inhibition of Drp1 ameliorated the mitochondrial ultrastructure at least via regulating PINK1 and Parkin in the mice of the PD model. This study also implicates that inhibition of Drp1 might impact mitophagy and recover mitochondrial homeostasis in PD. [ABSTRACT FROM AUTHOR]

Nine undescribed polyacetylated 18-norspirostanol saponins, trilliumosides A‒J, were obtained after a guidance based on a molecular networking strategy from the rhizomes of Trillium tschonoskii. Their structures were established by analysis of comprehensive spectroscopic data and chemical methods after their isolation in pure form. All isolated saponins were evaluated for their cytotoxicities against five selected human cancer cell lines (Huh7,A549,MCF-7,HepG2, and MOLT-4) and anti-inflammatory effects on a lipopolysaccharide (LPS)-stimulated NO production model in RAW264.7 macrophages. Trilliumoside D showed significant cytotoxicity against MOLT-4 cell lines with an IC 50 value of 1.0 ± 0.1 μM, whereas trilliumosides H and I displayed remarkable anti-inflammatory effects on NO production with inhibitory rates of 56.3 ± 1.5 and 56.2 ± 2.2% at the concentration of 1.0 μM, respectively. Image 1 • Molecular networking was used to capture 18-norspirostanol saponins form Trillium tschonoskii. • Nine undescribed polyacetylated 18-norspirostanol saponins were obtained. • Their structures were characterized by spectroscopic data and chemical methods. • Trilliumoside D was the most cytotoxic against MOLT-4 cells with an IC 50 value of 1.0 ± 0.1 μM. [ABSTRACT FROM AUTHOR]