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Substantial amounts of organo-pollutants, often persistent and toxic, are generated globally each year, posing a threat to soil, water, groundwater, and air. The pollutants encompass a wide range of substances from various sources, which include solid as well as liquid ones, such as landfill leachates and wastewaters. The compounds include paper and pulp mill byproducts, pharmaceuticals, diverse types of plastics, hydrocarbons, pigments, and dyes, as well as pesticides and insecticides. Fungal bioremediation stands out as a promising technology that uses the metabolic potential of fungi to eliminate or mitigate the impact of pollutants. Notably, species of the genus Pycnoporus exhibit significant capabilities for degrading a broad spectrum of toxic molecules. This degradation is facilitated by released ligninolytic enzymes, especially laccase, and cellular enzymes pertaining to the cytochrome P450 monooxygenase system. The laccase, which is overproduced by the genus Pycnoporus, is quite remarkable for its high redox potential. The objective of this review is to highlight the proficiency of the Pycnoporus genus in the degradation of pollutants in submerged and solid-state fermentation. Recent studies conducted over the past decade consistently highlight the Pycnoporus genus as a robust contender in the realm of white biotechnology.

This study aimed at investigating the chemical composition and a selected group of bioactivities of jatoba (Hymenaea courbaril L.) pod residue. An aqueous extract (deionized water; AE) and a hydroethanolic extract (ethanol: deionized water, 70:30 v/v; ETOH) were obtained via maceration. Ten phenolic compounds were characterized via LC-DAD-ESI/MSn: seven procyanidins, two quercetin derivatives and one taxifolin derivative, with dimers and trimers of procyanidins being the main components of both extracts. Total phenolic compound levels of 2.42 ± 0.06 and 11 ± 1 mg/g were found in AE and ETOH, respectively; however, only seven compounds were identified in ETOH. The jatoba pod residue extracts showed notable antioxidant activities: ETOH had greater antioxidant potential in the OxHLIA and DPPH assays (IC50 = 25.4 μg/mL and 0.71 μg/mL, respectively); however, EA demonstrated greater potential in the FRAP system (IC50 = 2001.0 µM TE/mg). Only AE showed antiproliferative potential, being effective against cell lines of gastric (GI50 = 35 ± 1 µg/mL) and breast (GI50 = 89 ± 4 µg/mL) adenocarcinomas. Likewise, only AE showed modest anti-inflammatory potential (IC50 = 225 ± 2 µg/mL) in mouse macrophages. Bacteriostatic effects against bacteria were exerted by both extracts. Enterococcus faecalis and Listeria monocytogenes (MICs = 2.5 mg/mL) were especially sensitive to the ETOH extract. Taken together, the results suggest potential for jatoba pod residue as a source of molecules with biological activities and with possible industrial applications.

Background and aim: The present study investigated the effects of orally administered α-tocopherol-loaded polycaprolactone nanoparticles on the articular inflammation and systemic oxidative status of middle-aged Holtzman rats with Freund's adjuvant-induced polyarthritis, a model for rheumatoid arthritis. Intraperitoneally administered free α-tocopherol provided the reference for comparison. Experimental procedure: Two protocols of treatment were followed: intraperitoneal administration of free α-tocopherol (100 mg/kg i.p.) or oral administration of free and nanoencapsulated α-tocopherol (100 mg/kg p.o.). Animals were treated during 18 days after arthritis induction. Results: Free (i.p.) and encapsulated α-tocopherol decreased the hind paws edema, the leukocytes infiltration into femorotibial joints and the mRNA expression of pro-inflammatory cytokines in the tibial anterior muscle of arthritic rats, but the encapsulated compound was more effective. Free (i.p.) and encapsulated α-tocopherol decreased the high levels of reactive oxygen species in the brain and liver, but only the encapsulated compound decreased the levels of protein carbonyl groups in these organs. Both free (i.p.) and encapsulated α-tocopherol increased the α-tocopherol levels and the ratio of reduced to oxidized glutathione in these organs. Conclusion: Both intraperitoneally administered free α-tocopherol and orally administered encapsulated α-tocopherol effectively improved inflammation and systemic oxidative stress in middle-aged arthritic rats. However, the encapsulated form should be preferred because the oral administration route does not be linked to the evident discomfort that is caused in general by injectable medicaments. Consequently, α-tocopherol-loaded polycaprolactone nanoparticles may be a promising adjuvant to the most current approaches aiming at rheumatoid arthritis therapy.

Pereskia aculeata Miller and Pereskia grandfolia Haw, known as ‘ora-pro-nobis’, are unconventional vegetables belonging to the Cactaceae family, native to the Americas and common in the northeast and southeast regions of Brazil. This review attempts to present a balanced account of both the methods used for obtaining extracts from the diverse parts of the plants and the results that were obtained in terms of their applicability to foods and other products with biological activities. Attention will also be devoted to the properties of their bioactives and their applications to real food products. Methods for obtaining extracts from the diverse parts of the plants will be analyzed, as well as the chemical nature of the bioactives that were hitherto identified. Next, the applicability of ora-pro-nobis in either its integral form or in the form of extracts or other products (mucilages) to the production of food and dietary supplements will be analyzed. The species have been extensively investigated during the last few decades. But, the determination of chemical structures is frequently incomplete and there is a need for new studies on texture determination and color evaluation. Further studies exploring the fruit and flowers of P. aculeata are also required.

The alkaloid boldine occurs in the Chilean boldo tree (Peumus boldus). It acts as a free radical scavenger and controls glycemia in diabetic rats. Various mechanisms have been proposed for this effect, including inhibited glucose absorption, stimulated insulin secretion, and increased expression of genes involved in glycemic control. Direct effects on glucose synthesis and degradation were not yet measured. To fill this gap, the present study is aimed at ensuring several metabolic pathways linked to glucose metabolism (e.g., gluconeogenesis) in the isolated perfused rat liver. In order to address mechanistic issues, energy transduction in isolated mitochondria and activities of gluconeogenic key enzymes in tissue preparations were also measured. Boldine diminished mitochondrial ROS generation, with no effect on energy transduction in isolated mitochondria. It inhibited, however, at least three enzymes of the gluconeogenic pathway, namely, phosphoenolpyruvate carboxykinase, fructose-bisphosphatase-1, and glucose 6-phosphatase, starting at concentrations below 50 μM. Consistently, in the perfused liver, boldine decreased lactate-, alanine-, and fructose-driven gluconeogenesis with IC50 values of 71.9, 85.2, and 83.6 μM, respectively. Conversely, the compound also increased glycolysis from glycogen-derived glucosyl units. The hepatic ATP content was not affected by boldine. It is proposed that the direct inhibition of hepatic gluconeogenesis by boldine, combined with the increase of glycolysis, could be an important event behind the diminished hyperglycemia observed in boldine-treated diabetic rats.

The white-rot fungus Pleurotus ostreatus was used for biological pretreatment of peach palm (Bactris gasipaes) lignocellulosic wastes. Non-treated and treated B. gasipaes inner sheaths and peel were submitted to hydrolysis using a commercial cellulase preparation from T. reesei. The amounts of total reducing sugars and glucose obtained from the 30 d-pretreated inner sheaths were seven and five times higher, respectively, than those obtained from the inner sheaths without pretreatment. No such improvement was found, however, in the pretreated B. gasipaes peels. Scanning electronic microscopy of the lignocellulosic fibers was performed to verify the structural changes caused by the biological pretreatments. Upon the biological pretreatment, the lignocellulosic structures of the inner sheaths were substantially modified, making them less ordered. The main features of the modifications were the detachment of the fibers, cell wall collapse and, in several cases, the formation of pores in the cell wall surfaces. The peel lignocellulosic fibers showed more ordered fibrils and no modification was observed after pre-treatment. In conclusion, a seven-fold increase in the enzymatic saccharification of the Bactris gasipaes inner sheath was observed after pre-treatment, while no improvement in enzymatic saccharification was observed in the B. gasipaes peel.

The actions of Eli Lilly-rDNA glucagon and Novo Nordisk-rDNA glucagon on glycogen catabolism and related parameters were investigated using the bivascularly perfused rat liver. The technique allows glucagon to be supplied to a selective portion of the hepatic periportal region (≈39%) when the former is infused into the hepatic artery in retrograde perfusion. Both glucagon preparations were equally effective in influencing metabolism (glucose output, glycolysis and O2 uptake) when supplied to all cells along the liver sinusoids. When only a selective periportal region of the liver was supplied with the hormone, however, the action of Novo Nordisk-rDNA glucagon was proportional to the accessible cell space, whereas the action of Eli Lilly-rDNA glucagon greatly exceeded the action that was expected for the accessible space. Chromatographically, both rDNA preparations were not pure, but their impurities were not the same. The impurities in Eli Lilly-rDNA glucagon resembled those found in the similarly acting pancreatic Eli Lilly glucagon. It was concluded that the space-extrapolating action of Eli Lilly-rDNA glucagon is caused by a yet-to-be-identified impurity. The hypothesis was raised that an impurity in certain glucagon preparations can enhance cell-to-cell propagation of the glucagon signal, possibly via gap junctional communication.

Abstract Background The stem bark aqueous alcohol extract of Poincianella pluviosa (PPSB extract) is rich in bioactives including gallic acid, gallic acid methyl ester, pyrogallol, ellagic acid, corilagin, 1,4,6-tri-O-galloyl-glucose, 1,2,3,6-tetra-O-galloyl-glucose, 1,2,3,4,6-penta-O-galloyl-glucose, tellimagrandin I, tellimagrandin II, mallotinic acid, mallotusinic acid, and geraniin. The aim of the present study was to evaluate the antioxidant activity of the PPSB extract as well as its inhibitory action on carbohydrate digestive enzymes relevant to type 2 diabetes. Results The PPSB extract was prepared using a mixture of 40% ethanol and 60% distilled water. The PPSB extract showed high antioxidant activities and inhibited several carbohydrate digestive enzymes. The IC50 values for inhibiting in vitro salivary amylase, pancreatic amylase, intestinal β-galactosidase and intestinal invertase were, respectively, 250 ± 15, 750 ± 40, 25 ± 5, and 75 ± 8 μg/mL. In vivo inhibition of the intestinal starch absorption was confirmed by determination of blood glucose levels in rats before and after administration of starch by gavage with or without different amounts of PPSB extract. Docking simulations performed on three different programs to rank the extract compounds most likely to bind to porcine pancreatic α-amylase suggest that geraniin is likely to be the P. pluviosa extract compound that presents the greatest binding potential to the pancreatic alpha-amylase. However, the total inhibitory action of the PPSB extract is likely to result from a summation of effects of several molecules. Furthermore, the PPSB extract did not present acute toxicity nor did it present mutagenic effects. Conclusion It can be concluded that the PPSB extract is potentially useful in controlling the postprandial glycaemic levels in diabetes. Further clinical studies with the extract are needed, however, to confirm its potential use in the management of type 2 diabetes.

The effect of farnesol, a sesquiterpene alcohol, on the production of laccases by Trametes versicolor and Pycnoporus sanguineus in pineapple waste solid-state fermentation was evaluated. Extracellular laccase production reached a maximum of 77.88 ± 5.62 U/g (236% above control) in farnesol-induced cultures of T. versicolor on the 17th day, whereas in a similar P. sanguineus culture, a maximal laccase activity of 130.95 ± 2.20 U/g (159% increase) was obtained on the 17th day. A single 45 KDa laccase was produced by both fungi under the influence of farnesol. These and other data allow us to conclude that farnesol acted as an inducer of the same form of laccase in both fungi. Farnesol disfavored fungal growth by increasing the lag phase, but it also clearly improved the oxidative state of the cultures. Contrary to the results obtained previously in submerged cultures, farnesol did not promote hyperbranching in the fungal mycelia. This is the first demonstration that farnesol is an excellent inducer of laccases in T. versicolor and P. sanguineus in solid-state cultivation. In quantitative terms, the results can be regarded as an excellent starting point for developing industrial or at least pre-industrial procedures to produce laccases using T. versicolor and P sanguineus under the stimulus of farnesol.

Conventional treatments for liver diseases are often burdened by side effects caused by chemicals. For minimizing this problem, the search for medicines based on natural products has increased. The objective of this review was to collect data on the potential hepatoprotective activity of plants of the Brazilian native flora. Special attention was given to the modes of extraction, activity indicators, and identification of the active compounds. The databases were Science direct, Pubmed, and Google Academic. Inclusion criteria were: (a) plants native to Brazil; (b) studies carried out during the last 15 years; (c) high-quality research. A fair number of communications met these criteria. Various parts of plants can be used, e.g., fruit peels, seeds, stem barks, and leaves. An outstanding characteristic of the active extracts is that they were mostly obtained from plant parts with low commercial potential, i.e., by-products or bio-residues. The hepatoprotective activities are exerted by constituents such as flavonoids, phenolic acids, vitamin C, phytosterols, and fructose poly- and oligosaccharides. Several Brazilian plants present excellent perspectives for the obtainment of hepatoprotective formulations. Very important is the economical perspective for the rural producers which may eventually increase their revenue by selling increasingly valued raw materials which otherwise would be wasted.

The peach palm (Bactris gasipaes Kunth) is a palm tree native to the Amazon region, with plantations expanding to the Brazilian Southwest and South regions. This work is a critical review of historical, botanical, social, environmental, and nutritional aspects of edible and nonedible parts of the plant. In Brazil, the importance of the cultivation of B. gasipaes to produce palm heart has grown considerably, due to its advantages in relation to other palm species, such as precocity, rusticity and tillering. The last one is especially important, as it makes the exploitation of peach palm hearts, contrary to what happens with other palm tree species, a non-predatory practice. Of special interest are the recent efforts aiming at the valorization of the fruit as a source of carotenoids and starch. Further developments indicate that the B. gasipaes lignocellulosic wastes hold great potential for being upcycled into valuable biotechnological products such as prebiotics, enzymes, cellulose nanofibrils and high fiber flours. Clean technologies are protagonists of the recovery processes, ensuring the closure of the product’s life cycle in a “green” way. Future research should focus on expanding and making the recovery processes economically viable, which would be of great importance for stimulating the peach palm production chain.

The pulp of the fruits of Juçara (Euterpes edulis Martius), a native tree of the Atlantic Rainforest of Brazil, is widely consumed thanks to its flavour and nutritional value. The industrial production of Juçara fruit pulp generates solid residues (peel) which are usually discarded. In this work, a hydroalcoholic extract from Juçara peel flour was evaluated for its phenolic profile as well as for its bioactivities. A total of nineteen phenolic compounds were identified in the Juçara peel flour. Among these, seventeen were non-anthocyanin phenolic compounds, namely two phenolic acids, four flavanonols, six flavones, and five flavonols; whereas the two anthocyanin molecules were cyanidin glycoside derivatives. The Euterpe edulis peel flour presented antioxidant activity and antibacterial potential but was not hepatotoxic. These observations corroborate the idea that this by-product could fit well into the circular bioeconomy concept, thus promoting the Juçara fruit production chain.

Pentagalloyl-glucose (PGG) occurs in many plants and possesses several therapeutic properties, including anti-diabetic ones. Based on the latter, the inhibitory action of PGG on α-amylases was investigated. PGG inhibited both the pancreatic and the salivary α-amylases. With starch as the substrate, complexation with the free enzyme form either predominates (pancreatic enzyme) or is the only complexation that is effectively allowed (salivary enzyme; competitive inhibition). This contrasts with a previous report on the salivary enzyme showing non-competitive inhibition when a synthetic substrate was used. PGG was less effective than acarbose as an inhibitor of α-amylases and presented a different binding pattern in terms of the aminoacyl residues involved. Finally, PGG also diminished the hyperglycemic excursion normally caused by starch administration when it was given to rats simultaneously to the polysaccharide. This suggests that PGG or foods and infusions rich in PGG could be helpful as adjuvants for maintaining normal glycemia.

Grape pomace is an agro-industrial residue produced worldwide. The purpose of this study was to identify and quantify the main phenolics present in an hydroalcohlic extract of a Merlot grape pomace and to investigate its effect on the oxidative and inflammatory states of adjuvant-induced arthritic rats. Daily doses of 250 mg of the extract per kg body weight were administered during 23 days. Several oxidative stress indicators in arthritic rats were maintained at their normal or closely normal levels in the plasma, liver and brain by the treatment. Additionally, the grape pomace also showed significant anti-inflammatory effects. From the 25 phenolics identified in the grape pomace extract the most abundant ones were catechin and catechin derivatives, which are possibly the most important antioxidant agents. The results suggest a potential applicability of the Merlot grape pomace hydroalcoholic extract in the improvement of the oxidative and inflammatory states in arthritic patients.

An investigation of the effects of an aqueous extract of Agaricus blazei, a medicinal mushroom, on the oxidative state of the brain and liver of rats during aging (7 to 23 months) was conducted. The treatment consisted in the daily intragastric administration of 50 mg/kg of the extract. The A. blazei treatment tended to maintain the ROS contents of the brain and liver at lower levels, but a significant difference was found only at the age of 23 months and in the brain. The TBARS levels in the brain were maintained at lower levels by the A. blazei treatment during the whole aging process with a specially pronounced difference at the age of 12 months. The total antioxidant capacity in the brain was higher in treated rats only at the age of 12 months. Compared with previous studies in which old rats (21 months) were treated during a short period of 21 days with 200 mg/kg, the effects of the A. blazei extract in the present study tended to be less pronounced. The results also indicate that the long and constant treatment presented a tendency of becoming less effective at ages above 12 months.

Methyl jasmonate (MeJA), common in the plant kingdom, is capable of reducing articular and hepatic inflammation and oxidative stress in adjuvant-induced arthritic rats. This study investigated the actions of orally administered MeJA (75−300 mg/kg) on inflammation, oxidative stress and selected enzyme activities in the brain of Holtzman rats with adjuvant-induced arthritis. MeJA prevented the arthritis-induced increased levels of nitrites, nitrates, lipid peroxides, protein carbonyls and reactive oxygen species (ROS). It also prevented the enhanced activities of myeloperoxidase and xanthine oxidase. Conversely, the diminished catalase and superoxide dismutase activities and glutathione (GSH) levels caused by arthritis were totally or partially prevented. Furthermore, MeJA increased the activity of the mitochondrial isocitrate dehydrogenase, which helps to supply NADPH for the mitochondrial glutathione cycle, possibly contributing to the partial recovery of the GSH/oxidized glutathione (GSSG) ratio. These positive actions on the antioxidant defenses may counterbalance the effects of MeJA as enhancer of ROS production in the mitochondrial respiratory chain. A negative effect of MeJA is the detachment of hexokinase from the mitochondria, which can potentially impair glucose phosphorylation and metabolism. In overall terms, however, it can be concluded that MeJA attenuates to a considerable extent the negative effects caused by arthritis in terms of inflammation and oxidative stress.

The particular characteristics of growth and development of mushrooms in nature result in the accumulation of a variety of secondary metabolites such as phenolic compounds, terpenes and steroids and essential cell wall components such as polysaccharides, b-glucans and proteins, several of them with biological activities. The present article outlines and discusses the available information about the protective effects of mushroom extracts against liver damage induced by exogenous compounds. Among mushrooms, Ganoderma lucidum is indubitably the most widely studied species. In this review, however, emphasis was given to studies using other mushrooms, especially those presenting efforts of attributing hepatoprotective activities to specific chemical components usually present in the mushroom extracts.

There are several claims about the beneficial effects of supplementing L-glutamine to both type 1 and type 2 diabetes. The purpose of the present study was to provide detailed knowledge about the fate of this amino acid in the liver, the first organ that receives the compound when ingested orally. The study was done using the isolated perfused rat liver, an experimental system that preserves the microcirculation of the organ and that allows to measured several parameters during steady-state and pre steady-state conditions. L-Glutamine was infused in the portal vein (5 mM) and several parameters were monitored. Livers from type 1 diabetic rats showed an accelerated response to L-glutamine infusion. In consequence of this accelerated response livers from type 1 diabetic rats presented higher rates of ammonia, urea, glucose and lactate output during the first 25-30 minutes following L-glutamine infusion. As steady-state conditions approached, however, the difference between type 1 diabetes and control livers tended to disappear. Measurement of the glycogen content over a period of 100 minutes revealed that, excepting the initial phase of the L-glutamine infusion, the increased glucose output in livers from type 1 diabetic rats was mainly due to accelerated glycogenolysis. Livers from type 2 diabetic rats behaved similarly to control livers with no accelerated glucose output but with increased L-alanine production. L-Alanine is important for the pancreatic β-cells and from this point of view the oral intake of L-glutamine can be regarded as beneficial. Furthermore, the lack of increased glucose output in livers from type 2 diabetic rats is consistent with observations that even daily L-glutamine doses of 30 g do not increase the glycemic levels in well controlled type 2 diabetes patients.

The fruit extracts of Citrus aurantium (bitter orange) are traditionally used as weight-loss products and as appetite supressants. An important fruit component is p-synephrine, which is structurally similar to the adrenergic agents. Weight-loss and adrenergic actions are always related to metabolic changes and this work was designed to investigate a possible action of the C. aurantium extract on liver metabolism. The isolated perfused rat liver was used to measure catabolic and anabolic pathways, including oxygen uptake and perfusion pressure. The C. aurantium extract and p-synephrine increased glycogenolysis, glycolysis, oxygen uptake and perfusion pressure. These changes were partly sensitive to a- and b-adrenergic antagonists. p-Synephrine (200 mM) produced an increase in glucose output that was only 15% smaller than the increment caused by the extract containing 196 mM p-synephrine. At low concentrations the C. aurantium extract tended to increase gluconeogenesis, but at high concentrations it was inhibitory, opposite to what happened with p-synephrine. The action of the C. aurantium extract on liver metabolism is similar to the well known actions of adrenergic agents and can be partly attributed to its content in p-synephrine. Many of these actions are catabolic and compatible with the weight-loss effects usually attributed to C. aurantium.

Pentachlorophenol (PCP) removal by Pleurotus pulmonarius grown in submerged cultures in the presence and absence of laccase inducers was studied in this work. When PCP was added to a final concentration of 25 mg·L-1 in submerged cultures actively producing laccase, 70% of the PCP was removed after 96 h. The removal of PCP was less than 20% in the cultures with low laccase activity. The results suggested that laccase played an important role in the biodegradation of PCP by P. pulmonarius and that for bioremediation purposes the fungus must be cultured under the conditions of active laccase production.

Glycogen levels and the energy status of livers from fasting rats with diabetes types 1 and 2 were measured. After a 24 h fast, the hepatic glycogen levels of rats with diabetes1 and diabetes2 were, 18.7 and 2.6 times higher, respectively, than those of livers from the normal rats. In diabetes1 rats, the glycogen levels decreased when the fasting period was extended to 48 and 72 h. The opposite occurred with the control and diabetes2 rats. Consistently, glucose release by the perfused livers from diabetes1 rats was considerably higher during at least 60 minutes after initiating perfusion. The hepatic ATP content of diabetes1 rats was similar to that of the control rats; in diabetes2 rats, the hepatic ATP content was increased. It could be concluded that regulation of glycogen deposition and degradation in rats with diabetes1 differed markedly from that of rats with diabetes2 which, in turn, behaved similarly to normal healthy rats.Teores de glicogênio e os estados energéticos de fígados de ratos com diabete dos tipos 1 e 2 foram medidos. Após um jejum de 24 horas os teores de glicogênio de ratos com diabete1 e diabete2 foram, respectivamente 18,7 e 2,6 vezes superiores àqueles de fígados de animais controle. Em ratos com diabete1 o conteúdo de glicogênio diminuiu quando o período de jejum foi prolongado para 48 e 72 horas. O oposto ocorreu em ratos controle e ratos com diabete2. Consistentemente, a liberação de glicose por fígados em perfusão isolada obtidos de ratos com diabete1 foi consideravelmente maior durante ao menos 60 minutos após o início da perfusão. O conteúdo hepático de ATP de ratos com diabete1 foi similar àquele de ratos controle; em ratos com diabete2 o conteúdo hepático de ATP foi maior. Pode-se concluir que a regulação da deposição e degradação do glicogênio em ratos com diabete1 difere marcadamente daquela de ratos com diabete2, os quais, por seu turno, comportam-se similarmente a ratos normais e saudáveis.

Ca2+ participates in the stimulation of hepatic gluconeogenesis by glucagon and there is evidence that Ca2+ fluxes are modified in arthritic rats. These findings raise the question whether hepatic gluconeogenesis in arthritic rats responds differently to glucagon and Ca2+. The experimental system was the isolated perfused rat liver. In the presence of Ca2+, stimulation of hepatic gluconeogenesis by glucagon in arthritic rats was equal to that in normal rats in absolute terms, but higher in relative terms (104.5 and 45.2%, respectively). In the absence of Ca2+, however, stimulation of hepatic gluconeogenesis by glucagon in arthritic rats was smaller in both absolute and relative terms (18.5 and 41.9%, respectively). It can be concluded that the Ca2+-dependent component of gluconeogenesis activation by glucagon is more important in arthritic than in normal rats.O Ca2+ participa do estímulo da neoglicogênese hepática pelo glucagon e há também indicações de que fluxos de Ca2+ são modificados em ratos artríticos. Estes dados permitem levantar a questão de se a neoglicogênese hepática em ratos artríticos responde diferentemente ao glucagon e ao Ca2+. O sistema experimental foi o fígado em perfusão isolada. Na presença de Ca2+, o estímulo da neoglicogênese hepática pelo glucagon em ratos artríticos foi quase igual a aquele encontrado em ratos normais em termos absolutos, mas maior em termos relativos (104,5 e 45,2%, respectiva-mente). Na ausência de Ca2+, no entanto, o estímu-lo da neoglicogênese hepática pelo glucagon em ratos artríticos foi menor em termos absolutos e relativos (18,5 e 41,9%, respectivamente). Pode-se concluir que o componente Ca2+-dependente do estímulo da neoglicogênese pelo glucagon é mais importante em ratos artríticos do que em ratos normais.