Differential expression of neuropeptide F in the digestive organs of female freshwater prawn, Macrobrachium rosenbergii, during the ovarian cycle.

Neuropeptide F is a key hormone that controls feeding in invertebrates, including decapod crustaceans. We investigated the differential expression of Macrobrachium rosenbergii neuropeptide F (MrNPF) in the digestive organs of female prawns, M. rosenbergii, during the ovarian cycle. By using RT-qPCR, the expression of MrNPF mRNA in the esophagus (ESO), cardia (CD), and pylorus (PY) of the foregut (FG) gradually increased from stage II and peaked at stage III. In the midgut (MG), hindgut (HG), and hepatopancreas (HP), MrNPF mRNA increased from stage I, reaching a maximal level at stage II, and declined by about half at stages III and IV (P < 0.05). In the ESO, CD, and PY, strong MrNPF-immunoreactivities were seen in the epithelium, muscle, and lamina propria. Intense MrNPF-ir was found in the MG cells and the muscular layer. In the HG, MrNPF-ir was detected in the epithelium of the villi and gland regions, while MrNPF-ir was also more intense in the F-, R-, and B-cells in the HP. However, we found little colocalization between the MrNPF and PGP9.5/ChAT in digestive tissues, implying that most of the positive cells might not be neurons but could be digestive tract-associated endocrine cells that produce and secrete MrNPF to control digestive organ functions in feeding and utilizing feed. Taken together, our first findings indicated that MrNPF was differentially expressed in digestive organs in correlation with the ovarian cycle, suggesting an important link between MrNPF, the physiology of various digestive organs in feeding, and possibly ovarian maturation in female M. rosenbergii.

Anatomical and molecular insights into the antennal gland of the giant freshwater prawn Macrobrachium rosenbergii.

In this study, the complex organization of the AnG in the giant freshwater prawn Macrobrachium rosenbergii was revealed using various techniques, including conventional histology, histochemistry, scanning electron microscopy, and X-ray tomography. The results showed the diversity of cells in the AnG and the detailed organization of the labyrinth's tubule into four radiated areas from the central to peripheral zones. The study also demonstrated the expression of some vertebrate kidney-associated homolog genes, aquaporin (AQP), solute carrier family 22 (SLC-22), nephrin, and uromodulin, in the AnG by qPCR. The result of in situ hybridization further showed the localization of SLC-22 and AQP transcript in the bladder and labyrinth's epithelium, specifically in regions 2, 3, and 4. Additionally, the study revealed neuropeptide expressions in the AnG by qPCR and in situ hybridization, i.e., crustacean hyperglycemic hormone (CHH) and molt inhibiting hormone (MIH), implying that the AnG may have a role in hormone production. Moreover, male and female prawns exhibited different levels of AQP, SLC-22, nephrin, and CHH expressions during the premolt and intermolt stages, suggesting a crucial role relevant to the molting stages. In conclusion, this study clarified the complex structure of the AnG in M. rosenbergii and demonstrated for the first time the expression of vertebrate kidney-associated genes and the possible endocrine role of the AnG. Further investigation is needed to clarify the role of these genes, particularly during ecdysis. The implications of these findings could significantly advance our understanding of the AnG in decapod crustaceans.

The presence and distribution of gamma-aminobutyric acid and dopamine during the developmental stages of the sea cucumber, Holothuria scabra, with emphasis on settlement organs.

In the sea cucumber, Holothuria scabra, the competent larvae require main settlement organs (SOs), including the ciliary bands (CiBs), tentacles (Ts), podia (PDs), and cues from neurotransmitters, including gamma-aminobutyric acid (GABA) and dopamine (DA), for successful settlement. In the present study, we investigated the spatial distribution of GABA and DA in the developmental stages of H. scabra, with special emphasis on SOs by detecting immunoreactivity (-ir) against these two neurotransmitters. Strong GABA-ir and DA-ir cells and fibers were specifically detected in several SO structures, including CiBs, CiB cells (CiBCs), and long cilia (LCi), of H. scabra larvae. Additionally, we found intense GABA-ir and DA-ir cells in the epithelial lining of bud-papillae (BP) and mesothelium (Me) in the stem (S) region of Ts in larvae and juveniles. Intense GABA-ir and DA-ir were observed in the epineural nerve plexus (ENP) and hyponeural nerve plexus (HNP) of Ts in H. scabra pentactula and juvenile stages. Staining for these two neurotransmitters was particularly intense in the PDs and their nerve fibers. We also found significant changes in the numbers of GABA-ir and DA-ir-positive cells and intensities in the CiBs, Ts, and PDs during the developmental stages. Taken together, we are the first to report on the existence and distribution of GABAergic and dopaminergic systems in structures associated with the settlement. Our findings provide new and important insights into the possible functions of these two neurotransmitters in regulating the settlement of this sea cucumber species.

Anti-Parkinson Effects of Holothuria leucospilota-Derived Palmitic Acid in Caenorhabditis elegans Model of Parkinson's Disease.

Parkinson's disease (PD) is the second most common neurodegenerative disease which is still incurable. Sea cucumber-derived compounds have been reported to be promising candidate drugs for treating age-related neurological disorders. The present study evaluated the beneficial effects of the Holothuria leucospilota (H. leucospilota)-derived compound 3 isolated from ethyl acetate fraction (HLEA-P3) using Caenorhabditis elegans PD models. HLEA-P3 (1 to 50 µg/mL) restored the viability of dopaminergic neurons. Surprisingly, 5 and 25 µg/mL HLEA-P3 improved dopamine-dependent behaviors, reduced oxidative stress and prolonged lifespan of PD worms induced by neurotoxin 6-hydroxydopamine (6-OHDA). Additionally, HLEA-P3 (5 to 50 µg/mL) decreased α-synuclein aggregation. Particularly, 5 and 25 µg/mL HLEA-P3 improved locomotion, reduced lipid accumulation and extended lifespan of transgenic C. elegans strain NL5901. Gene expression analysis revealed that treatment with 5 and 25 µg/mL HLEA-P3 could upregulate the genes encoding antioxidant enzymes (gst-4, gst-10 and gcs-1) and autophagic mediators (bec-1 and atg-7) and downregulate the fatty acid desaturase gene (fat-5). These findings explained the molecular mechanism of HLEA-P3-mediated protection against PD-like pathologies. The chemical characterization elucidated that HLEA-P3 is palmitic acid. Taken together, these findings revealed the anti-Parkinson effects of H. leucospilota-derived palmitic acid in 6-OHDA induced- and α-synuclein-based models of PD which might be useful in nutritional therapy for treating PD.

Anti-Obesity Effects of Marine Macroalgae Extract Caulerpa lentillifera in a Caenorhabditis elegans Model.

Obesity is a multifactorial disease characterized by an excessive accumulation of fat, which in turn poses a significant risk to health. Bioactive compounds obtained from macroalgae have demonstrated their efficacy in combating obesity in various animal models. The green macroalgae Caulerpa lentillifera (CL) contains numerous active constituents. Hence, in the present study, we aimed to elucidate the beneficial anti-obesity effects of extracts derived from C. lentillifera using a Caenorhabditis elegans obesity model. The ethanol (CLET) and ethyl acetate (CLEA) extracts caused a significant decrease in fat consumption, reaching up to approximately 50-60%. Triglyceride levels in 50 mM glucose-fed worms were significantly reduced by approximately 200%. The GFP-labeled dhs-3, a marker for lipid droplets, exhibited a significant reduction in its level to approximately 30%. Furthermore, the level of intracellular ROS displayed a significant decrease of 18.26 to 23.91% in high-glucose-fed worms treated with CL extracts, while their lifespan remained unchanged. Additionally, the mRNA expression of genes associated with lipogenesis, such as sbp-1, showed a significant down-regulation following treatment with CL extracts. This finding was supported by a significant decrease (at 16.22-18.29%) in GFP-labeled sbp-1 gene expression. These results suggest that C. lentillifera extracts may facilitate a reduction in total fat accumulation induced by glucose through sbp-1 pathways. In summary, this study highlights the anti-obesity potential of compounds derived from C. lentillifera extracts in a C. elegans model of obesity, mediated by the suppression of lipogenesis pathways.

Neuroprotection of Andrographolide against Neurotoxin MPP+-Induced Apoptosis in SH-SY5Y Cells via Activating Mitophagy, Autophagy, and Antioxidant Activities.

Parkinson's disease (PD) is associated with dopaminergic neuron loss and alpha-synuclein aggregation caused by ROS overproduction, leading to mitochondrial dysfunction and autophagy impairment. Recently, andrographolide (Andro) has been extensively studied for various pharmacological properties, such as anti-diabetic, anti-cancer, anti-inflammatory, and anti-atherosclerosis. However, its potential neuroprotective effects on neurotoxin MPP+-induced SH-SY5Y cells, a cellular PD model, remain uninvestigated. In this study, we hypothesized that Andro has neuroprotective effects against MPP+-induced apoptosis, which may be mediated through the clearance of dysfunctional mitochondria by mitophagy and ROS by antioxidant activities. Herein, Andro pretreatment could attenuate MPP+-induced neuronal cell death that was reflected by reducing mitochondrial membrane potential (MMP) depolarization, alpha-synuclein, and pro-apoptotic proteins expressions. Concomitantly, Andro attenuated MPP+-induced oxidative stress through mitophagy, as indicated by increasing colocalization of MitoTracker Red with LC3, upregulations of the PINK1-Parkin pathway, and autophagy-related proteins. On the contrary, Andro-activated autophagy was compromised when pretreated with 3-MA. Furthermore, Andro activated the Nrf2/KEAP1 pathway, leading to increasing genes encoding antioxidant enzymes and activities. This study elucidated that Andro exhibited significant neuroprotective effects against MPP+-induced SH-SY5Y cell death in vitro by enhancing mitophagy and clearance of alpha-synuclein through autophagy, as well as increasing antioxidant capacity. Our results provide evidence that Andro could be considered a potential supplement for PD prevention.

Characterization, expression and function of the pyrokinins (PKs) in the giant freshwater prawn, Macrobrachium rosenbergii.

Pyrokinins (PKs) are neuropeptides that have been found to regulate a variety of physiological activities including reproduction in various insect and crustacean species. However, the reproductive roles of PKs in the giant freshwater prawn, Macrobrachium rosenbergii, have not yet been investigated. In this study, we identified the MroPK gene from next-generation sequence resources, which encodes a MroPK precursor that shares a high degree of conservation with the C-terminal sequence of FxPRLamide in other arthropods. MroPK is expressed within most tissues, except the hepatopancreas, stomach and gill. Within developing ovarian tissue, MroPK expression was found to be significantly higher during the early stages (stages 1-2) compared with the late stages (stages 3-4), and could be localized to the oogonia, previtellogenic and early vitellogenic oocytes. A role for PK in M. rosenbergii reproduction was supported following experimental administration of MroPK to ovarian explant cultures, which led to an increase in the production of progesterone and estradiol and upregulation of expression of steroidogenesis-related genes (3ß-HSD and 17ß-HSD) and vitellogenin (Vg). Together, these results support a role for MroPK in regulating ovarian maturation via steroidogenesis.

Ultrastructure of cells constituting lymphoid tubules and circulating hemocytes in Penaeus monodon.

The two main groups of cells in the lymphoid tubule wall of Penaeus monodon are fixed cells and migrating hemocytes. Fixed cells include endothelial, stromal, and capsular cells. Together, they form the scaffold that defines the structure of the lymphoid tubule and provide physical support as well as a niche for transmigrating hemocytes. The luminal surface of lymphoid tubule was lined by elongated, spindle-shaped endothelial cells with a centrally located nucleus and rather thick plasma membrane. Stromal cells were the smallest type of fixed cell. They are stellate cells located between the inner endothelial and outer capsular cells. These cells formed a cyto-reticular network for migrating hemocytes. Capsular cells have a flattened and irregular shape with a ruffled border with long filamentous microvilli. The nucleus is centrally located within a small mass of cytoplasm. Together they form the outermost layer of the lymphoid tubular wall. Transmigrating hemocytes within the lymphoid tubules, as opposed to circulating hemocytes, were classified into hyaline (HH), small granular (SGH) and large granular (LGH) hemocytes. The HH have very few granules and a few cytoplasmic organelles, reflecting low synthetic activity. The granular hemocytes (SGH and LGH), despite being different in size, have similar ultrastructural characteristics. They contain high amounts of rough endoplasmic reticulum, ribosomes, mitochondria, and three types of granules. These characteristics implicate their higher synthetic as well as immunologic activities. Based on these characteristics we believe that all the hemocytes belong to a single line of cell differentiation.

Ethyl Acetate Extract of Marine Algae, Halymenia durvillei, Provides Photoprotection against UV-Exposure in L929 and HaCaT Cells.

Halymenia durvillei is a red alga distributed along the coasts of Southeast Asian countries including Thailand. Previous studies have shown that an ethyl acetate fraction of H. durvillei (HDEA), containing major compounds including n-hexadecanoic acid, 2-butyl-5-hexyloctahydro-1H-indene, 3-(hydroxyacetyl) indole and indole-3-carboxylic acid, possesses high antioxidant and anti-lung cancer activities. The present study demonstrated that HDEA could protect mouse skin fibroblasts (L929) and human immortalized keratinocytes (HaCaT) against photoaging due to ultraviolet A and B (UVA and UVB) by reducing intracellular reactive oxygen species (ROS) and expressions of matrix metalloproteinases (MMP1 and MMP3), as well as increasing Nrf2 nuclear translocation, upregulations of mRNA transcripts of antioxidant enzymes, including superoxide dismutase (SOD), heme oxygenase (HMOX) and glutathione S-transferase pi1 (GSTP1), and procollagen synthesis. The results indicate that HDEA has the potential to protect skin cells from UV irradiation through the activation of the Nrf2 pathway, which leads to decreasing intracellular ROS and MMP production, along with the restoration of skin collagen.

Holothuria scabra Extract Induces Cell Apoptosis and Suppresses Warburg Effect by Down-Regulating Akt/mTOR/HIF-1 Axis in MDA-MB-231 Breast Cancer Cells.

INTRODUCTION: Cancer cells utilize the modified glucose metabolism known as Warburg effect, with lactate production as the end product. In the search for alternative therapy, the body wall of sea cucumbers contains various substances with pharmacological activities. Herein, we investigate the effect of Holothuria scabra extract on the viability and Warburg effect of aggressive breast cancer cells. METHODS: Body wall of H. scabra was extracted using 95% ethanol. Triple-negative breast cancer cells, MDA-MB-231, were treated with the extract at various concentrations under normoglycemic and hyperglycemic conditions. Cytotoxicity test was performed using MTT assay. Apoptotic proteins were quantified using Western blot. Apoptotic cells were stained with Hoechst 33342. Lactate production was determined using L-lactate assay kit. RESULTS: By MTT assay, H. scabra extract suppressed the viability of breast cancer cells in a dose-dependent and time-dependent manner by enhancing apoptosis, indicated by a marked increase of proapoptotic Bax and pro-caspase three expressions, and decreased expression of anti-apoptotic Bcl-2. The extract could reduce hexokinase II expression, leading to reduced lactate production by blocking the Akt/mTOR/HIF-1 axis. DISCUSSION: Overall findings indicated that H. scabra extract could be a possible therapeutic against breast cancer progression in patients with hyperglycemia, for instance, diabetes mellitus.

The oxytocin/vasopressin-like peptide receptor mRNA in the central nervous system and ovary of the blue swimming crab, Portunus pelagicus.

The authors recently reported the presence and distribution of oxytocin/vasopressin-like peptide in Portunus pelagicus as well as demonstrated its function to inhibit ovarian steroid release (Saetan et al., 2018). Here, the full-length receptor of this peptide, namely oxytocin/vasopressin-like peptide receptor (PpelOT/VP-like peptide receptor) is reported. The coding region of the PpelOT/VP-like peptide receptor contained 1497 bp which translationally corresponded to 499 amino acids. Sequence analysis revealed its seven transmembrane characteristics, with -two N-linked glycosylation residues located before the first transmembrane domain (TM I). The phylogenetic tree revealed that the PpelOT/VP-like peptide receptor was placed in the group of invertebrate OT/VP-like receptors, and was clearly distinguishable from the V1R, V2R and OTR of vertebrates. Also, this receptor gene transcript was detected in several organs of the blue swimming crab with highest abundance found in brain tissue. In situ hybridization exhibited its distribution in all neuronal clusters of the eyestalk, brain, ventral nerve cord (VNC), as well as in the ovary. Comparative gene expressions between this receptor and its corresponding peptide in immature and mature female crabs revealed no significant difference of the PpelOT/VP-like peptide receptor gene expression in the central nervous system (CNS) and ovary. In contrast, the PpelOT/VP-like peptide gene was shown to significantly express higher in the VNC of immature crabs and in the ovary of mature crabs. Changes in expression of this peptide gene, but not its receptor, might result in ovarian steroid release inhibition. However, the detailed mechanism of this peptide in reproduction regulation will be included in our further studies.

Beneficial Effects of Cyclic Ether 2-Butoxytetrahydrofuran from Sea Cucumber Holothuria scabra against Aß Aggregate Toxicity in Transgenic Caenorhabditis elegans and Potential Chemical Interaction.

The pathological finding of amyloid-ß (Aß) aggregates is thought to be a leading cause of untreated Alzheimer's disease (AD). In this study, we isolated 2-butoxytetrahydrofuran (2-BTHF), a small cyclic ether, from Holothuria scabra and demonstrated its therapeutic potential against AD through the attenuation of Aß aggregation in a transgenic Caenorhabditis elegans model. Our results revealed that amongst the five H. scabra isolated compounds, 2-BTHF was shown to be the most effective in suppressing worm paralysis caused by Aß toxicity and in expressing strong neuroprotection in CL4176 and CL2355 strains, respectively. An immunoblot analysis showed that CL4176 and CL2006 treated with 2-BTHF showed no effect on the level of Aß monomers but significantly reduced the toxic oligomeric form and the amount of 1,4-bis(3-carboxy-hydroxy-phenylethenyl)-benzene (X-34)-positive fibril deposits. This concurrently occurred with a reduction of reactive oxygen species (ROS) in the treated CL4176 worms. Mechanistically, heat shock factor 1 (HSF-1) (at residues histidine 63 (HIS63) and glutamine 72 (GLN72)) was shown to be 2-BTHF's potential target that might contribute to an increased expression of autophagy-related genes required for the breakdown of the Aß aggregate, thus attenuating its toxicity. In conclusion, 2-BTHF from H. scabra could protect C. elegans from Aß toxicity by suppressing its aggregation via an HSF-1-regulated autophagic pathway and has been implicated as a potential drug for AD.

An ethyl-acetate fraction of Holothuria scabra modulates inflammation in vitro through inhibiting the production of nitric oxide and pro-inflammatory cytokines via NF-κB and JNK pathways.

Sea cucumber, Holothuria scabra, is an echinoderm marine animal that has long been used as a traditional therapeutic in various diseases due to its chemical composition and protein enrichment. Many researchers have extensively studied the efficacy of sea cucumber extracts for many health benefits in recent years. Inflammation is a complex process involved in pro-/anti-inflammatory cytokine products. However, the role of the H. scabra extracts in anti-inflammation and its molecular regulations has not been apparently elucidated yet. In this study, we investigated the anti-inflammatory effect of H. scabra extracts by using lipopolysaccharide (LPS) from E. coli to induce an inflammatory response in RAW264.7 macrophage. It was found that ethyl acetate fraction of H. scabra extracts (EAHS) inhibited pro-inflammatory cytokines synthesis at both the transcriptional and translational levels, notably nitric oxide (NO), inducible nitric oxide synthase (iNOS), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and prostaglandin E2 (PGE2). In addition, EAHS was able to downregulate IκB/NF-κB, and JNK expressions. These effects may be influenced by high contents of phenolic compound and triterpene glycosides in EAHS. Therefore, EAHS might have the potential to be developed as a natural anti-inflammatory agent.

Distribution of neuropeptide F in the ventral nerve cord and its possible role on testicular development and germ cell proliferation in the giant freshwater prawn, Macrobrachium rosenbergii.

Neuropeptide F in invertebrates is a homolog of neuropeptide Y in mammals and it is a member of FMRFamide-related peptides. In arthropods, such as insects, there are two types of neuropeptide F comprising long neuropeptide F (NPF) and short neuropeptide F (sNPF). Both NPFs are known to play a crucial role in the regulations of foraging, feeding-related behaviors, circadian rhythm, stress responses, aggression and reproduction in invertebrates. We have earlier found that in the giant freshwater prawn, Macrobrachium rosenbergii, there are three isoforms of NPF and four isoforms of sNPF and that NPFs are expressed in the eyestalks and brain. In the present study, we investigate further the tissue distribution of NPF-I in the ventral nerve cord (VNC) and its role in the development of testes in small male (SM) Macrobrachium rosenbergii. By immunolocalization, using the rabbit polyclonal antibody against NPF-I as a probe, we could detect NPF-I immunoreactivity in the neuropils and neuronal clusters of the subesophageal ganglia (SEG), thoracic ganglia (TG) and abdominal ganglia (AG) of the SM prawns. In functional assays, the administrations of synthetic NPF-I (KPDPTQLAAMADALKYLQELDKYYSQVSRPRFamide) and sNPF (APALRLRFamide) peptides significantly increased the growth rates of SM prawns and significantly increased the gonadosomatic index (GSI) and proliferations of early germ cells in the seminiferous tubules of their testes. It is, therefore, suggestive that NPFs may play critical roles in energy homeostasis towards promoting growth as well as testicular development in prawns that could be applied in the aquaculture of this species.

Saponin-enriched extracts from body wall and Cuvierian tubule of Holothuria leucospilota reduce fat accumulation and suppress lipogenesis in Caenorhabditis elegans.

BACKGROUND: Saponins have been shown to possess many pharmacological properties, including altered fat metabolism. The black sea cucumber, Holothuria leucospilota, is a marine animal that contains a specialized organ called a Cuvierian tubule that produces and secrete the bioactive saponins into the tubules and body wall. Therefore, the aims of this study are to investigate the anti-obesity effect of saponins extracted from body wall and Cuvierian tubules of H. leucospilota. RESULTS: The butanol extracts of H. leucospilota body wall and Cuvierian tubules containing high amounts of saponins significantly reduced fat deposition and triglyceride levels in Caenorhabditis elegans fed with 50 mmol L-1 glucose. Moreover, the saponin-enriched extracts of H. leucospilota significantly restored the lifespan of 2% glucose-fed worms (18.71%). Green fluorescence protein-labeled sbp-1 gene expression and nuclear translocation of daf-16 were also significantly decreased in H. leucospilota treatment. The saponin-enriched extracts downregulated the messenger RNA expressions of genes involved in fat storage and metabolism, including sbp-1, cebp, and daf-16 but upregulated the expression of nhr-49 gene. CONCLUSION: Our results suggest that H. leucospilota-derived saponins may mediate the reduction of glucose-induced fat accumulation through sbp-1, cebp, daf-16 and nhr-9 pathways. Therefore, the H. leucospilota extracts could be used as nutraceuticals for anti-obesity prevention. © 2019 Society of Chemical Industry.

Inhibitory effect of a reproductive-related serpin on sperm trypsin-like activity implicates its role in sperm maturation of Penaeus monodon.

In a number of marine animals, sperm serine proteases are important for fertilization. Penaeus monodon sperm require trypsin-like activity for a complete acrosome reaction, which exclusively occurs in sperm residing in the female thelycum. In this study, a complete cDNA sequence of reproductive tract-related Serine protease inhibitor (rrPmserpin) was identified. The longest open reading frame was composed of 1,366 nucleotides encoding 402 amino acids with a predicted pI of 6.86 and molecular mass of 44.88 kDa. The signal peptide cleavage site was identified as the 17th amino acid residue in the amino-terminus, and two potential N-glycosylation sites were predicted as post-translation modifications. A conserved reactive loop and fold similarities, identified through three-dimensional modeling, suggested that this gene is a member of the serpin family. The expression of rrPmserpin mRNA was prominent in the reproductive organs, including the testis, vas deferens, terminal ampoule containing the spermatophore, and the female thelycum. Inhibitory activity of recombinant rrPmSERPIN-6His was revealed from the negative correlation between the abundance of rrPmserpin mRNA and sperm trypsin-like activities, along with its inhibitory effects on chymotrypsin, trypsin, and thelycal proteases. Therefore, our results suggest that rrPmserpin participates in the regulation of the activity of a sperm protease and the decapacitation process.

Distribution and dynamic expression of serotonin and dopamine in the nervous system and ovary of Holothuria scabra during ovarian maturation.

In the present study, the distribution and dynamic expression of serotonin and dopamine in the nervous system and ovary of the sea cucumber, Holothuria scabra, during different ovarian stages were investigated. We found that serotonin-immunoreactivity was more intense in the neurons and neuropils of the outer ectoneural part, the inner hyponeural part, and the wall of hyponeural canal of radial nerve cord during the mature stages of ovarian cycle, whereas dopamine-immunoreactivity was detected at a higher intensity in these tissues during the early stages. Both neurotransmitters were detected in the ectoneural part of the nerve ring. In the ovary, serotonin intensity was more intense in the cytoplasm of late oocytes, while dopamine-immunoreactivity was more intense in the early stages. The changes in the levels serotonin in the radial nerve cord and oocytes are incremental towards the late stages of ovarian maturation. In contrast, dopamine levels in the nervous tissues and oocytes were more intense in early stages and became decremental towards the late stages. These findings suggest that serotonin and dopamine may have opposing effects on ovarian development in this sea cucumber species.

Differential expressions of estrogen and progesterone receptors in endometria and cyst walls of ovarian endometrioma from women with endometriosis and their responses to depo-medroxyprogesterone acetate treatment.

BACKGROUND: Depo-medroxyprogesterone acetate (DMPA) is an injectable progestin contraceptive that provides a highly effective reduction of pelvic pain in women with endometriosis. Despite its wide use to treat pain associated with endometriosis, its precise mechanisms of action remain unclear. The aims of this study were to investigate the differential expressions of estrogen receptors (ERs), and progesterone receptors (PRs) in endometria and ovarian endometrioma cyst walls of women with endometriosis with and without DMPA treatment. METHODS: Endometria and cyst walls of endometrioma were obtained from 25 to 45 year-old women who suffered from endometriosis and had ovarian endometrioma with the size ≥3 cm. The expression levels of ERs and PRs and the numbers of ER- and PR-positive cells before and after treatment with DMPA were evaluated by Western blot, real-time PCR, and immunohistochemistry. RESULTS: The levels of ERα and ERß expression, their corresponding mRNAs, and numbers of ERα- and ERß-immunoreactive cells in stroma and glands of endometria of the DMPA group were significantly decreased when compared with those of the untreated groups (p < 0.05). In contrast, the levels of PRA/B expression and numbers of PRA/B positive cells in stroma and number of PRB positive cells in stroma and endometrial glands were significantly increased in endometria of the DMPA group when compared with those of the untreated groups. However, in cyst wall the expression levels of these proteins, their corresponding mRNAs, and immonoractive cells were low compared to those in endometria, and DMPA-treatment did not cause any significant changes in these parameters. CONCLUSION: These data indicated that DMPA could upregulate the expressions of PRA/B and down-regulate ERα and ERß in endometria but not in cyst walls from women with endometriosis.

Holothuria scabra extracts exhibit anti-Parkinson potential in C. elegans: A model for anti-Parkinson testing.

OBJECTIVES: Parkinson's disease (PD) is associated with aggregation of α-synuclein and selective death of dopaminergic (DA) neurons in the substantia nigra, thereby leading to cognitive and motor impairments. Nowadays, the drugs commonly used for PD treatment, such as levodopa, provide only symptomatic relief. Therefore, seeking new drugs against PD, especially from plants and marine organisms, is one of the major research areas to be explored. This study aimed to investigate the anti-Parkinson activity of the extracts from the sea cucumber, Holothuria scabra, by using Caenorhabditis elegans as a model. METHODS: H. scabra was solvent-extracted and subdivided into six fractions including whole body-ethyl acetate (WBEA), body wall-ethyl acetate (BWEA), viscera-ethyl acetate (VIEA), whole body-butanol (WBBU), body wall-butanol (BWBU), and viscera-butanol (VIBU). The extracts were tested in C. elegans BZ555 strain expressing the green fluorescent protein (GFP) specifically in the DA neurons and NL5901 strain expressing human α-synuclein in the muscle cells. RESULTS: WBEA, BWEA, and WBBU fractions of H. scabra extracts at 500 µg/ml significantly attenuated DA neuron-degeneration induced by selective cathecholamine neurotoxin 6-hydroxydopamine (6-OHDA) in the BZ555 strain. Moreover, the extracts also reduced α-synuclein aggregation and restored lipid content in NL5901, as well as improved food-sensing behavior and prolonged lifespan in the 6-OHDA-treated wild-type strain. DISCUSSION: The study indicated that the H. scabra extracts have anti-Parkinson potential in the C. elegans model. These findings encourage further investigations on using the H. scabra extract, as well as its active constituent compounds, as a possible preventive and/or therapeutic intervention against PD.

Potential of recombinant 2-Cys peroxiredoxin protein as a vaccine for Fasciola gigantica infection.

Helminth 2-cys peroxiredoxin (Prx) is a major antioxidant enzyme that protects parasites against hydrogen peroxide-generating oxidative stress from the hosts' immune responses. This enzyme has been found in all stages of the tropical liver fluke, Fasciola gigantica. To investigate the potential of the recombinant F. gigantica Prx-2 (rFgPrx-2) as a vaccine candidate, vaccine trials in mice were carried out. In this study, the ICR mice were immunized with rFgPrx-2 combined with Freund's adjuvant and infected with F. gigantica metacercariae. The vaccine efficacy was estimated by quantitate fluke recovery, antibody levels and liver function. The protection by rFgPrx-2 against F. gigantica infection was achieved at 43-46% compared with adjuvant-infected and non-immunized-infected control groups, respectively. The vaccine elicited both Th1 and Th2 humoral immune responses with predominance of Th2 as indicated by the higher level of IgG1 in sera of immunized mice. However, the levels of liver damage markers, serum glutamate oxalic transaminase (SGOT) and serum glutamic pyruvate transaminase (SGPT) in rFgPrx-2 immunized group did not show significant difference in comparison with the controls. This study suggested that rFgPrx-2 may have a potential as a vaccine against tropical fasciolosis.