The effects of laser acupuncture on the modulation of cartilage extracellular matrix macromolecules in rats with adjuvant-induced arthritis.

OBJECTIVES: Articular cartilage damage related to irreversible physical disability affects most patients with chronic rheumatoid arthritis (RA). Strategies targeting the preservation of cartilage function are needed. Laser acupuncture (LA) can be an emerging alternative therapy for RA; however, its molecular mechanism underlying the beneficial effect on cartilage has not been elucidated. This study aimed to examine the potential chondroprotective effects of LA on extracellular matrix (ECM) macromolecules and proinflammatory cytokines in the articular cartilage of adjuvant-induced arthritis (AIA) rats and explore its related mechanisms. DESIGN: Monoarthritis was induced in adult male Sprague-Dawley rats (250-300 g) via intraarticular injection of complete Freund's adjuvant (CFA) into the tibiotarsal joint. Animals were treated with LA at BL60 and KI3 acupoints three days after CFA administration with a 780 nm GaAlAs laser at 15 J/cm2 daily for ten days. The main outcome measures including paw circumference, paw withdrawal threshold, histopathology and immunoassays of tumor necrosis factor-α (TNF-α), collagen type II (CoII), cartilage oligomeric matrix protein (COMP) were analyzed. RESULTS: LA significantly reduced ankle edema and inflammation-induced hyperalgesia in AIA rats (P < 0.05). Moreover, the TNF-α levels were significantly decreased while CoII, COMP and proteoglycans proteins were significantly enhanced following LA stimulation of the AIA cartilage compared to those treated with sham-LA (P < 0.05). CONCLUSIONS: LA attenuates cartilage degradation in AIA rat by suppressing TNF-α activation and up-regulating ECM macromolecules, suggesting LA might be of potential clinical interest in RA treatment.

Differential responses to ocean acidification between populations of Balanophyllia elegans corals from high and low upwelling environments.

Ocean acidification (OA), the global decrease in surface water pH from absorption of anthropogenic CO2 , may put many marine taxa at risk. However, populations that experience extreme localized conditions, and are adapted to these conditions predicted in the global ocean in 2,100, may be more tolerant to future OA. By identifying locally adapted populations, researchers can examine the mechanisms used to cope with decreasing pH. One oceanographic process that influences pH is wind-driven upwelling. Here we compare two Californian populations of the coral Balanophyllia elegans from distinct upwelling regimes, and test their physiological and transcriptomic responses to experimental seawater acidification. We measured respiration rates, protein and lipid content, and gene expression in corals from both populations exposed to pH levels of 7.8 and 7.4 for 29 days. Corals from the population that experiences lower pH due to high upwelling maintained the same respiration rate throughout the exposure. In contrast, corals from the low upwelling site had reduced respiration rates, protein content and lipid-class content at low pH exposure, suggesting they have depleted their energy reserves. Using RNA-Seq, we found that corals from the high upwelling site upregulated genes involved in calcium ion binding and ion transport, most likely related to pH homeostasis and calcification. In contrast, corals from the low upwelling site downregulated stress response genes at low pH exposure. Divergent population responses to low pH observed in B. elegans highlight the importance of multi-population studies for predicting a species' response to future OA.

Metabolic plasticity in development: Synergistic responses to high temperature and hypoxia in zebrafish, Danio rerio.

This study investigated interactions of temperature and hypoxia on metabolic plasticity and regulation in zebrafish, Danio rerio, in the first week of development. Larval morphometry, oxygen consumption, and metabolic responses to acute changes in temperature and oxygen were measured in larvae reared under four conditions, including control (28°C and partial pressures of oxygen [PO2] of 21 kPa), high temperature (31°C), hypoxia (11 kPa), and the two stressors combined. Rearing conditions did not result in consistent morphometric changes; substantial metabolic adjustments, however, were evident. While acute temperature increase resulted in elevated oxygen consumption, with a Q10 of 2.2 ± 0.08, early-staged larvae were able to compensate to chronic temperature rise as routine metabolic rates did not differ between 28°C and 31°C chronic treatments. In contrast, larval responses to chronic and acute hypoxia were similar, with ∼30% decrease in metabolic rates from normoxic values at both temperatures. Further, prior exposure to chronic hypoxia in conjunction with acute high temperature increased Q10 by a factor of 2.5 from 2.2 ± 0.08 to 5.6 ± 0.19. Metabolic suppression by acute hypoxia was independent of any prior exposure conditions. In short, results from this study showed that zebrafish larvae exhibited surprising temperature resilience and metabolic plasticity to a 3°C temperature rise even in their first week of life. Yet exposure to a second stressor (hypoxia) resulted in elevated sensitivity to temperature change that may lead to bioenergetic imbalance due to synergetic effects of temperature and hypoxia on metabolic rates.

Onset and early development of hypoxic ventilatory responses and branchial neuroepithelial cells in Xenopus laevis.

Onset and ontogeny of the O2 chemoreceptive control of ventilation was investigated in Xenopus laevis. The density and size of branchial serotonin-immunoreactive neuroepithelial cells (5-HT-IR NECs) were also determined using confocal immunofluorescent microscopy. Larvae started gill ventilation at 3 days post-fertilization (dpf), and, at this early stage, acute hypoxic exposure produced an increase in frequency from 28 ± 4 to 60 ± 2 beats x min⁻¹. Concurrent with the onset of ventilatory responses, 5-HT-IR NECs appeared in the gill filament bud. Lung ventilation began at 5 dpf and exhibited a 3-fold increase in frequency during acute hypoxia. At 10 dpf, gill ventilatory sensitivity to hypoxia increased, as did NEC density, from 15 ± 1 (5 dpf) to 29 ± 2 (10 dpf) cells x mm of filament⁻¹. Unlike ventilation frequency, gill ventilation amplitude and lung expired volume were unaltered by acute hypoxia. Chronic exposure to moderate hypoxia, at a P(O2) of 110 mmHg, attenuated acute responses to moderate hypoxia at 10 and 14 dpf but had no effect at more severe hypoxia or at other stages. Chronic hypoxia also stimulated 5-HT-IR NECs growth at 21 dpf. Collectively, larvae at 5 dpf exhibited strong O2-driven gill and lung ventilatory responses, and between 10 and 21 dpf, the early hypoxic responses can be shaped by the ambient P(O2).

Prophylaxis of experimentally induced calcium oxalate nephrolithiasis in rats by Zhulingtang, a traditional Chinese herbal formula.

BACKGROUND: Zhulingtang (ZLT), a traditional Chinese medicine formula, was used to evaluate the antilithic effects of experimentally induced calcium oxalate (CaOx) nephrolithiasis in ethylene glycol (EG)-fed rats. MATERIALS AND METHODS: A total of 35 male Sprague-Dawley rats were randomly divided into 4 groups. Rats in group 1 (n = 8) served as the normal control. Rats in group 2 (n = 11) were treated with gastric gavages of starch as placebo and 0.75% EG as a stone inducer. Rats in group 3 (n = 8) were given 0.75% EG and a low dose (305 mg/kg) of ZLT. Rats in group 4 (n = 8) were treated with EG and a high dose (915 mg/kg) of ZLT. Twenty-four-hour urine and blood samples were collected at the beginning and at the end of the experiment for biochemical analysis. The histological appearances of the kidneys were observed under a polarized light microscope, and the crystal deposits were evaluated by a semiquantitative scoring method, computer assisted with ImageScoring software. RESULTS: Our results revealed that rats fed with 0.75% EG for 4 weeks successfully produced renal deposition of CaOx. The severities of crystal deposition were significantly reduced in the 2 ZLT-fed groups compared with the placebo group (p = 0.025 and 0.047, respectively). Rats in the low-dose ZLT and placebo groups exhibited significantly lower serum phosphorus in comparison with the control rats (p = 0.005 and 0.03, respectively). Rats of the placebo group (EG + starch) encountered growth retardation, with their body weights slowly increasing, expressed as 160.63 +/- 23.06 g, compared with 179.63 +/- 13.41 g in normal rats (p < 0.001). CONCLUSION: ZLT reduced the severity of CaOx crystallization and slowed down the body weight loss effects. Therefore, the traditional Chinese medicine herbal formula ZLT may be an effective reagent for renal stone prophylaxis. Although the mechanism of ZLT in crystal inhibition remains unclear, macromolecules may be involved.

A traditional Chinese herbal antilithic formula, Wulingsan, effectively prevents the renal deposition of calcium oxalate crystal in ethylene glycol-fed rats.

We investigated the effects of a traditional Chinese herbal formula, Wulingsan (WLS), on renal stone prevention using an ethylene glycol-induced nephrocalcinosis rat model. Forty-one male Sprague-Dawley (SD) rats were divided into four groups. Group 1 (n=8) was the normal control; group 2 (n=11) served as the placebo group, and received a gastric gavage of starch and 0.75% ethylene glycol (EG) as a stone inducer; group 3 received EG and a low dose of WLS (375 mg/kg); and group 4 received EG and a high dose of WLS (1,125 mg/kg). Baseline and final 24 h urine samples were collected individually; biochemical data of urine and serum were also obtained at the beginning and at the end of the experiment. After 4 weeks, animals were killed and kidneys were harvested. The kidney specimens were examined by polarized light microscopy and the crystal deposits were evaluated by a semi-quantitative scoring method using computer software (ImageScoring). The results revealed that the rats of placebo group gained the least significant body weight; in contrast, the rats of WLS-fed groups could effectively reverse it. The placebo group exhibited lower levels of free calcium (p=0.059) and significantly lower serum phosphorus (p=0.015) in urine than WLS-fed rats. Histological findings of kidneys revealed tubular destruction, damage and inflammatory reactions in the EG-water rats. The crystal deposit scores dropped significantly in the WLS groups, from 1.40 to 0.46 in the low-dose group and from 1.40 to 0.45 in the high-dose group. Overall, WLS effectively inhibited the deposition of calcium oxalate (CaOx) crystal and lowered the incidence of stones in rats (p=0.035). In conclusion, WLS significantly reduced the severity of calcium oxalate crystal deposits in rat kidneys, indicating that Wulingsan may be an effective antilithic herbal formula.

Epithelial Ca(2+) channel expression and Ca(2+) uptake in developing zebrafish.

The purpose of the present work was to study the possible role of the epithelial Ca(2+) channel (ECaC) in the Ca(2+) uptake mechanism in developing zebrafish (Danio rerio). With rapid amplification of cDNA ends, full-length cDNA encoding the ECaC of zebrafish (zECaC) was cloned and sequenced. The cloned zECaC was 2,578 bp in length and encoded a protein of 709 amino acids that showed up to 73% identity with previously described vertebrate ECaCs. The zECaC was found to be expressed in all tissues examined and began to be expressed in the skin covering the yolk sac of embryos at 24 h postfertilization (hpf). zECaC-expressing cells expanded to cover the skin of the entire yolk sac after embryonic development and began to occur in the gill filaments at 96 hpf, and thereafter zECaC-expressing cells rapidly increased in both gills and yolk sac skin. Corresponding to ECaC expression profile, the Ca(2+) influx and content began to increase at 36-72 hpf. Incubating zebrafish embryos in low-Ca(2+) (0.02 mM) freshwater caused upregulation of the whole body Ca(2+) influx and zECaC expression in both gills and skin. Colocalization of zECaC mRNA and the Na(+)-K(+)-ATPase alpha-subunit (a marker for mitochondria-rich cells) indicated that only a portion of the mitochondria-rich cells expressed zECaC mRNA. These results suggest that the zECaC plays a key role in Ca(2+) absorption in developing zebrafish.

cDNA cloning and expression of the cardiac Na+/Ca2+ exchanger from Mozambique tilapia (Oreochromis mossambicus) reveal a teleost membrane transporter with mammalian temperature dependence.

The complete cDNA sequence of the tilapia cardiac Na(+)/Ca2+ exchanger (NCX-TL1.0) was determined. The 3.1-kb transcript encodes a protein 957 amino acids in length, with a predicted signal peptide cleaved at residue 31 and two potential N-glycosylation sites in the extracellular N terminus. Hydropathy analysis and sequence comparison predicted a mature protein with nine transmembrane-spanning segments, consistent with the structural topologies of other known mammalian and teleost NCX isoforms. Overall sequence comparison shows high identity to both trout NCX-TR1.0 ( approximately 81%) and mammalian NCX1.1 ( approximately 73%), and phylogenetic analyses confirmed its identity as a member of the NCX1 gene family, expressing exons A, C, D, and F in the alternative splice site. Sequence identity is even higher in the alpha-repeats, the exchanger inhibitory peptide (XIP) site, and Ca(2+)-binding domains, which is reflected in the functional and regulatory properties of tilapia NCX-TL1.0. When NCX-TL1.0 was expressed in Xenopus oocytes and the currents were measured in giant excised patches, they displayed both positive regulation by Ca2+ and Na(+)-dependent inactivation in a manner similar to trout NCX-TR1.0. However, tilapia NCX-TL1.0 exhibited a relatively high sensitivity to temperature compared with trout NCX-TR1.0. Whereas trout NCX-TR1.0 currents displayed activation energies of approximately 7 kJ/mol, tilapia NCX-TL1.0 currents showed mammal-like temperature dependence, with peak and steady-state current activation energies of 53 +/- 9 and 67 +/- 21 kJ/mol, respectively. Using comparative sequence analysis, we highlighted 10 residue positions in the N-terminal domain of the NCX that, in combination, may confer exchanger temperature dependence through subtle changes in protein flexibility. Tilapia NCX-TL1.0 represents the first non-mammalian NCX to exhibit a mammalian temperature dependence phenotype and will prove to be a useful model in defining the interplay between molecular flexibility and stability in NCX function.