Therapeutic ultrasound ameliorates hyperalgesia and edema on CFA-induced persistent inflammatory response in mice

Abstract Background: The present study investigated the effects of pulsed and continuous ultrasound (USP and USC) in edema and hyperalgesia after chronic inflammatory process induced by Complete Freund's Adjuvant-CFA and analyzing the relationship of the application frequency of ultrasound, in pro- and anti-inflammatory cytokine production. Methods: Forty-five animals were divided into 9 groups; all animals from groups 2 to 9 were subjected to a persistent inflammation model induced by CFA in mice. We report the effects and the underlying action mechanisms of USP and USC in the animals which were irradiated two, three or five times a week on the left hind paw. The analyses performed in this study were: evaluation of hind paw edema through the plethysmometer, evaluation of thermal hyperalgesia through withdrawal test using a water container at 44.5°C (± 0.5°C), and the plantar region of the left paw which was removed for analysis of cytokines. Results: Our results showed that USP and USC consistently reduced paw edema, and pulsed ultrasound showed a higher significant effect than the continuous mode. Moreover, groups with irradiation frequency of five times a week presented an inhibition of the edema, and groups with frequency of three or two times a week reduced mainly hyperalgesia, in comparison with the control group. The beneficial effects of the US then seem to be associated with upregulation of anti- and pro-inflammatory mediators, such as IL-10 and IL-6, respectively. Conclusion: This study provided evidence that ultrasound constitutes an important non-pharmacological intervention for the management of inflammatory and pain states.

Disruption of glucose tolerance caused by glucocorticoid excess in rats is partially prevented, but not attenuated, by arjunolic acid.

Arjunolic acid (AA) obtained from plants of the Combretaceae family has shown anti-diabetic effects. Here, we analyzed whether the diabetogenic effects of dexamethasone (DEX) treatment on glucose homeostasis may be prevented or attenuated by the concomitant administration of AA. Adult Wistar rats were assigned to the following groups: vehicle-treated (Ctl), DEX-treated (1 mg/kg body weight intraperitoneally for 5 days) (Dex), AA-treated (30 mg/kg body weight by oral gavage twice per day) (Aa), AA treatment previous to and concomitant to DEX treatment (AaDex), and AA treatment after initiation of DEX treatment (DexAa). AA administration significantly ameliorated (AaDex) (P>0.05), but did not attenuate (DexAa), the glucose intolerance induced by DEX treatment. AA did not prevent or attenuate the elevation in hepatic glycogen and triacylglycerol content caused by DEX treatment. All DEX-treated rats exhibited hepatic steatosis that seemed to be more pronounced when associated with AA treatment given for a prolonged period (AaDex). Markers of liver function and oxidative stress were not significantly altered among the groups. Therefore, AA administered for a prolonged period partially prevents the glucose intolerance induced by DEX treatment, but it fails to produce this beneficial effect when given after initiation of GC treatment. Since AA may promote further hepatic steatosis when co-administered with GCs, care is required when considering this phytochemical as a hypoglycemiant and/or insulin-sensitizing agent.

Antimycobacterial activity of the fractions and compounds from Scutia buxifolia

The antimycobacterial activity of Scutia buxifolia Reissek, Rhamnaceae, leaves extracts and fractions were evaluated for the first time. Four compounds were identified, flavonoids (quercetin and quercitrin) and phenolic acids (gallic and caffeic acids) and quantified by HPLC-DAD. Promising anti-Mycobacterium smegmatis activity was observed with ethyl acetate extract (MIC 312.50 µg/mL) and their fractions (MIC values ranging from 78.12 to above 312.50 µg/mL). The fractions III and VI of S. buxifolia leaves showed a high level of activity against M. smegmatis (MIC 78.12 and 156.25 µg/mL, respectively), M. tuberculosis (MIC 156.25 µg/mL) and M. avium (MIC 312.50 µg/mL), whereas to the other fractions the values varied from 312.50 to 1250.00 µg/mL against these strains. The better MIC result was associated with two fractions that contain bigger amounts of quercetin, quercitrin, gallic and caffeic acids. The results provided evidence that the studied plants fractions might be potential sources of new antimicrobial drug.

The plants of the genus Phyllanthus as a potential source of new drugs

The plants of the genus Phyllanthus (Euphorbiaceae) comprise about 550 to 750 species which are widely distributed in most tropical and subtropical countries. About 200 species are believed to occur in the Americas, mainly in the Caribbean and Brazil. The plants of the genus Phyllanthus have long been used in folk medicine to treat, among others, kidney and urinary bladder disorders, intestinal infections, diabetes and hepatitis B. In recent years, substantial progress in chemical and pharmacological studies, and a few clinical studies of some Phyllanthus species, were made. This review discusses the current knowledge gained by the in vitro and in vivo pharmacological and biochemical studies performed with the extracts and the main active constituents isolated from different species of plants of the genus Phyllanthus. Data available in the literature strongly support the idea that the extract and some constituents isolated from these plants, including flavanoids, tannins, alkaloids, coumarins, lignans and terpenes, account for their reported antinociceptive, anti-inflammatory, antiviral, antispasmodic and antiallergic properties. In addition, some of these compounds were found to interact with most key enzymes, such as aldose reductase, angiotensin converting enzyme, mitochondrial ATPase, both cyclo- and lipooxygenases, phospholipase A2, tyrosine kinase, reverse transcriptase, and phosphodiesterases. The complex mechanism of action of such compounds could explain, at least in part, the wide therapeutic use of the plants of the genus Phyllanthus in folk medicine. Thus, the plants of the genus Phyllanthus present potential therapeutic interest as a source of new drugs.