Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Ivo Rotkvic is active.

Publication


Featured researches published by Ivo Rotkvic.


European Journal of Pharmacology | 1997

The influence of a novel pentadecapeptide, BPC 157, on NG-nitro-l-arginine methylester and l-arginine effects on stomach mucosa integrity and blood pressure

Predrag Sikiric; Sven Seiwerth; Željko Grabarević; Rudolf Rucman; Marijan Petek; Vjekoslav Jagić; Branko Turkovic; Ivo Rotkvic; Stjepan Mise; Ivan Zoricic; Paško Konjevoda; Darko Perovic; Ljubica Jurina; Jadranka Separovic; Miro Hanževački; Branka Artuković; Mirna Bratulić; Marina Tišljar; Miro Gjurašin; Pavao Miklić; Dinko Stančić-Rokotov; Zoran Slobodnjak; Nikola Jelovac; Anton Marovic

The known effects of a novel stomach pentadecapeptide BPC157 (10 microg or 10 ng/kg), namely its salutary activity against ethanol (96%, i.g.)-induced gastric lesions (simultaneously applied i.p.) and in blood pressure maintenance (given i.v.), were investigated in rats challenged with a combination of N(G)-nitro-L-arginine methylester (L-NAME) (5 mg/kg i.v.), a competitive inhibitor of endothelium nitric oxide (NO)-generation and NO precursor, L-arginine (200 mg/kg i.v.) (D-arginine was ineffective). In the gastric lesions assay, NO agents were given 5 min before ethanol injury and BPC 157 medication. Given alone, BPC157 had an antiulcer effect, as did L-arginine, but L-NAME had no effect. L-NAME completely abolished the effect of L-arginine, whereas it only attenuated the effect of BPC 157. After application of the combination of L-NAME + L-arginine, the BPC157 effect was additionally impaired. In blood pressure studies, compared with L-arginine, pentadecapeptide BPC 157 (without effect on basal normal values) had both a mimicking effect (impaired L-NAME-blood pressure increase, when applied prophylactically and decreased already raised L-NAME values, given at the time of the maximal L-NAME-blood pressure increase (i.e., 10 min after L-NAME)) and preventive activity (L-arginine-induced moderate blood pressure decrease was prevented by BPC 157 pretreatment). When BPC 157 was given 10 min after L-NAME + L-arginine combination, which still led to a blood pressure increase, its previously clear effect (noted in L-NAME treated rats) disappeared. In vitro, in gastric mucosa from rat stomach tissue homogenates, BPC 157, given in the same dose (100 microM) as L-arginine, induced a comparable generation of NO. But, BPC 157 effect could not be inhibited by L-NAME, even when L-NAME was given in a tenfold (100 versus 1000 microM) higher dose than that needed for inhibition of the L-arginine effect. NO synthesis was blunted when the pentadecapeptide BPC 157 and L-arginine were combined. In summary, BPC 157 could interfere with the effects of NO on both gastric mucosal integrity and blood pressure maintenance in a specific way, especially with L-arginine, having a more prominent and/or particularly different effect from that of NO.


Life Sciences | 1994

The beneficial effect of BPC 157, a 15 amino acid peptide BPC fragment, on gastric and duodenal lesions induced by restraint stress, cysteamine and 96% ethanol in rats. A comparative study with H2 receptor antagonists, dopamine promotors and gut peptides

Predrag Sikiric; Sven Seiwerth; Zeljko Grabarevic; Marijan Petek; Rudolf Rucman; Branko Turkovic; Ivo Rotkvic; Vjekoslav Jagić; Marko Duvnjak; Stjepan Mise; Sanja Djačić; Jadranka Separovic; Marija Veljača; Ahmet Sallmani; Marko Banić; Tomislav Brkić

The protection of stomach and duodenum in conjecture with anti-inflammatory effect was demonstrated for a novel 15 amino acid peptide, coded BPC 157, a fragment of the recently discovered gastric juice peptide BPC. BPC 157 (i.p./i.g.) was investigated in rats in comparison with several reference standards in three experimental ulcer models (48 h-restraint stress, subcutaneous cysteamine, intragastrical 96% ethanol ulcer tests) (pre-/co-/post-treatment). Only BPC 157 regimens were consistently effective in all of the tested models. On the other hand, bromocriptine, amantadine, famotidine, cimetidine and somatostatin were ineffective (restraint stress). A dose-dependent protection (cysteamine) and/or partial positive effect (related to treatment conditions) (ethanol), was obtained with glucagon, NPY and secretin whereas CCK/26-30/was not effective. Based on Monastral blue studies BPC 157 beneficial effect appears to be related to a strong endothelial protection.


Burns | 2001

Pentadecapeptide BPC 157 cream improves burn-wound healing and attenuates burn-gastric lesions in mice

Darko Mikus; P Sikiric; Sven Seiwerth; A Petricevic; Gorana Aralica; N Druzijancic; Rudolf Rucman; Marijan Petek; Biserka Pigac; Darko Perovic; M Kolombo; Neven Kokić; S Mikus; Božidar Duplančić; I Fattorini; Branko Turkovic; Ivo Rotkvic; Stjepan Mise; Ingrid Prkačin; Paško Konjevoda; N Stambuk; Tomislav Anic

The effects of the gastric pentadecapeptide BPC 157 were investigated when administered topically or systemically in burned mice. This agent is known to have a beneficial effect in a variety of models of gastrointestinal lesions, as well as on wound or fracture healing. Deep partial skin thickness burns (1.5x1.5 cm) covering 20% of total body area, were induced under anesthesia on the back of mice by controlled burning and gastric lesions were assessed 1, 2, 3, 7, 14 and 21 days following injury. The first application of BPC 157 was immediately following burning, and thereafter, once daily, until 24 h before sacrifice. In the initial experiments, exposure to direct flame for 5 s, the BPC 157 was applied at 10 microg or 10 ng/kg b.w. intraperitoneally (i.p.) by injection or alternatively, topically, at the burn, as a thin layer of cream (50 microg of BPC 157 dissolved in 2 ml of distilled water was mixed with 50 g of commercial neutral cream (also used as local vehicle-control)), while silver sulfadiazine 1% cream was a standard agent acting locally. Others received no local medication: they were treated i.p. by injection of distilled water (distilled water-control) or left without any medication (control). In subsequent experiments involving deeper burns (direct flame for 7 s), BPC 157 creams (50 microg, 5 microg, 500 ng, 50 ng or 5 ng of BPC 157 dissolved in 2 ml of distilled water was mixed with 50 g of commercial neutral cream), or vehicle as a thin layer of cream, were applied topically, at the burn. Compared with untreated controls, in both experiments, in the BPC 157 cream-treated mice all parameters of burn healing were improved throughout the experiment: less edema was observed and inflammatory cell numbers decreased. Less necrosis was seen with an increased number of capillaries along with an advanced formation of dermal reticulin and collagen fibers. An increased number of preserved follicles were observed. Two weeks after injury, BPC 157 cream-treated mice completely reversed the otherwise poor re-epithelization ratio noted in the untreated control or mice treated with vehicle only. Tensiometry investigation showed an increased breaking strength and relative elongation of burned skin, while water content in burned skin decreased. This was, however, not the case with the vehicle or silver sulfadiazine. Relative to the control values, in silver sulfadiazine cream-treated mice, only collagen fiber formation was increased, in addition to a decreased inflammatory cell number. Relative to control values, BPC 157 given i.p. decreased the number of inflammatory cells, lowered water content in burned skin, and raised breaking strength and relative elongation of burned skin during tensiometry. Through the experimental period, gastric lesions were continuously noted in all thermally injured mice left without local medication and they were consistently attenuated only by BPC 157 treatments: either given i.p. (at either dose), or given locally (at either concentration). Other treatments (i.e. local treatment with silver sulfadiazine cream or neutral cream in mice subjected for 5 s to direct flame), led to only poor, if any attenuation. This stable gastric pentadecapeptide appears to be active and gives a stimulation to burn healing at the defect site. The agent may act by causing an upregulation of the growth factors, as well as influencing other local factors.


Digestive Diseases and Sciences | 1996

Beneficial effect of a novel pentadecapeptide BPC 157 on gastric lesions induced by restraint stress, ethanol, indomethacin, and capsaicin neurotoxicity

Predrag Sikiric; Sven Seiwerth; Željko Grabarević; Rudolf Rucman; Marijan Petek; Vjekoslav Jagić; Branko Turkovic; Ivo Rotkvic; Stjepan Mise; Ivan Zoricic; Miroslav Gjurasin; Paško Konjevoda; Jadranka Separovic; Danica Ljubanović; Branka Artuković; Mirna Bratulić; Marina Tišljar; Ljubica Jurina; Gojko Buljat; Pavao Miklić; Anton Marovic

Very recently, the integrity of capsaicin somatosensory neurons and their protection were suggested to be related to the activity in nociception of a newly discovered 15-amino acid peptide, BPC 157, shown to have strong beneficial effect on intestinal and liver lesions. Therefore, from this viewpoint, we have studied the gastroprotective effect of the pentadecapeptide BPC 157, on gastric lesions produced in rats by 96% ethanol, restraint stress, and indomethacin. The possible involvement of sensory neurons in the salutary actions of BPC 157 (10µg/kg, 10 ng/kg intraperitoneally) was studied with capsaicin, which has differential effects on sensory neurons: a high dose in adult (125 mg/kg subcutaneously, 3 months old) or administration (50 mg/kg subcutaneously) to neonatal animals (age of the 7 days) destroys sensory fibers, whereas a low dose (500µg/kg intraperitoneally) activates neurotransmitter release and protective effects on the mucosa. In the absence of capsaicin, BPC 157 protected gastric mucosa against ethanol, restraint, and indomethacin application. In the presence of neurotoxic doses of capsaicin, the negative influence of capsaicin on restraint, ethanol, or indomethacin lesions consistently affected salutary activity of BPC 157. However, BPC 157 protection was still evident in the capsaicin-treated rats (either treated as adults or as newborns) in all of these assays. Interestingly, after neonatal capsaicin treatment, a complete abolition of BPC gastroprotection was noted if BPC 157 was applied as a single nanogram-regimen, but the mucosal protection was fully reversed when the same dose was used daily. In line with the excitatory dose of capsaicin the beneficial effectiveness of BPC 157 appears to be increased as well. Taken together, these data provide evidence for complex synergistic interaction between the beneficial effectiveness of BPC 157 and peptidergic sensory afferent neuron activity.


Life Sciences | 1993

Hepatoprotective effect of BPC 157, A 15-aminoacid peptide, on liver lesions induced by either restraint stress or bile duct and hepatic artery ligation or CCl4 administration. A comparative study with dopamine agonists and somatostatin

Predrag Sikiric; Sven Seiwerth; Zeljko Grabarevic; Rudolf Rucman; Marijan Petek; Ivo Rotkvic; Branko Turkovic; Vjekoslav Jagić; Boris Mildner; Marko Duvnjak; Zarko Danilović; Marko Kolega; Ahmet Sallmani; Sanja Dacic; Milan Dodig; Nada Lang; Jadranka Separovic; V. Corić; Velimir Šimičević; Krešimir Bulić; Marija Veljača; Nevena Skroza; Marko Banić; Tomislav Brkić; Gojko Buljat; Stjepan Mise; Drazen Lucinger; Miljenko Bura

The hepatoprotective effects of a newly synthesized 15 amino acid fragment code named BPC 157 was evaluated in comparison with the reference standards (bromocriptine, amantadine and somatostatin) in various experimental models of liver injury in rats: 24 h-bile duct+hepatic artery ligation 48 h-restraint stress and CCl4 administration. BPC 157 administered either intragastrically or intraperitoneally, significantly prevented the development of liver necrosis or fatty changes in rats subjected to 24 h bile duct + hepatic artery ligation, 48 h-restraint stress, CCl4 treatment (1 ml/kg i.p., sacrifice 48 h thereafter). The other reference drugs had either little or no protective actions in these models. Noteworthy, the laboratory test results for bilirubin, SGOT, SGPT fully correlated with the macro/microscopical findings. Thus, on the basis of consistent protective effect of BPC 157, possible clinical application in liver diseases is now warranted.


Journal of Physiology-paris | 1997

Pentadecapeptide BPC 157 positively affects both non-steroidal anti-inflammatory agent-induced gastrointestinal lesions and adjuvant arthritis in rats

P Sikiric; Sven Seiwerth; Zeljko Grabarevic; Rudolf Rucman; Marijan Petek; Vjekoslav Jagić; Branko Turkovic; Ivo Rotkvic; Stjepan Mise; Ivan Zoricic; Paško Konjevoda; Darko Perovic; Velimir Šimičević; Jadranka Separovic; Miroslav Hanzevacki; Danica Ljubanović; Branka Artuković; Mirna Bratulić; Marina Tišljar; B Rekic; Miroslav Gjurasin; Pavle Miklic; Gojko Buljat

Besides a superior protection of the pentadecapeptide BPC 157 (an essential fragment of an organoprotective gastric juice peptide BPC) against different gastrointestinal and liver lesions, an acute anti-inflammatory and analgetic activity was also noted. Consequently, its effect on chronic inflammation lesions, such as adjuvant arthritis, and non-steroidal anti-inflammatory agents (NSAIAs)-induced gastrointestinal lesions was simultaneously studied in rats. In gastrointestinal lesions (indomethacin (30 mg/kg s.c.), aspirin (400 mg/kg i.g.) and diclofenac (125 mg/kg i.p.) studies, BPC 157 (10 micrograms or 10 ng/kg i.p.) was regularly given simultaneously and/or 1 h prior to drug application (indomethacin). In the adjuvant arthritis (tail-application of 0.2 mL of Freunds adjuvant) studies (14 days, 30 days, 1 year) BPC 157 (10 micrograms or 10 ng/kg i.p.), it was given as a single application (at 1 h either before or following the application of Freunds adjuvant) or in a once daily regimen (0-14th day, 14-30th day, 14th day-1 year). Given with the investigated NSAIAs, BPC 157 consistently reduced the otherwise prominent lesions in the stomach of the control rats, as well as the lesions in the small intestine in the indomethacin groups. In the adjuvant arthritis studies, the lesions development seems to be considerably reduced after single pentadecapeptide medication, and even more attenuated in rats daily treated with BPC 157. As a therapy of already established adjuvant arthritis, its salutary effect consistently appeared already after 2 weeks of medication and it could be clearly seen also after 1 year of application. Taking together all these results, the data likely point to a special anti-inflammatory and mucosal integrity protective effect.


European Journal of Pharmacology | 1986

Dopamine antagonists induce gastric lesions in rats

Predrag Sikiric; Juraj Geber; Dragutin Ivanović; Veljko Gjuriš; Milica Tućan-Foretić; Stjepan Mise; Branimir Cvitanović; Ivo Rotkvic

Gastric lesions were provoked in all rats that had received intraperitoneally a single dose of the dopamine antagonists haloperidol, metoclopramide or domperidone 24 h before. Dose-dependence was demonstrated for haloperidol. This drug induced gastric lesions as early as 90 min after its application. The ulcerogenic effect of haloperidol was completely prevented or markedly reduced by simultaneous applications of dopamine agonists bromocriptine or L-dopa. We conclude that the model of gastric lesions induced by dopamine antagonists could be successfully applied in further investigations of the role of dopamine in the pathogenesis of ulcer disease.


Digestive Diseases and Sciences | 1997

Pentadecapeptide BPC 157, Cimetidine, Ranitidine, Bromocriptine, and Atropine Effect in Cysteamine Lesions in Totally Gastrectromized Rats (A Model for Cytoprotective Studies)

Predrag Sikiric; Darko Mikus; Sven Seiwerth; Zeljko Grabarevic; J Peric; Paško Konjevoda; Darko Perovic; Ljubica Jurina; Stipislav Jadrijević; Nikola Jelovac; Pavao Miklić; Gojko Buljat; Rudolf Rucman; Marijan Petek; Vjekoslav Jagić; Branko Turkovic; Ivo Rotkvic; Stjepan Mise; Ivan Zoricic; Miro Hanzevacki; Jadranka Separovic; Miroslav Gjurasin; Anton Marovic

A superior effectiveness in various lesionassays was noted for the novel pentadecapeptide BPC 157,originated from human gastric juice protein (BPC) andclaimed to be a cytoprotective agent. From this viewpoint, as a previously untreatedexperimental improvement to create an acid-freeenvironmental for cytoprotection studies, totalgastrectomy was done 24 hr before the ulcerogenicprocedure. In the absence of stomach and gastric acid, the damagingeffects of cysteamine (400 mg/kg subcutaneously, death24 hr thereafter), to date thought to be an acid-relatedduodenal ulcerogen, and the BPC 157 cytoprotective effect (10 mug or 10 ng/kg intraperitoneally)were further challenged. BPC 157 was compared withreference agents [cimetidine (50), ranitidine (10),omeprazole (10), bromocriptine (10) and atropine (10) (mg/kg intraperitoneally, 1 hr beforecysteamine] known to be also cytoprotective. In naiverats, with intact stomach, all of them showed a strongbeneficial effect. Interestingly, in gastrectomizedanimals, the application of BPC 157 or the referenceagents before cysteamine significantly prevented theotherwise severe duodenal lesion development noted inthe control gastrectomized cysteamine rats. In groups without cysteamine, no lesions were noted(laparotomy, gastrectomy only, 24 or 48 hr postsurgicalperiod), nor was lesion potentiation seen incysteamine-treated laparotomized animals. In summary,these findings -- equal damaging effect ofcysteamine and equal protection of pentadecapeptide BPC157 and reference agents in gastrectomized and rats withintact stomach -- seem to be particularly relevantfor a cytoprotective viewpoint. Without a stomach,the cysteamine damaging effect was convincingly definedas an essential gastric acid-independent injury(analogous to ethanol gastric lesions). Likewise, a high “cytoprotective capacity,”apparently acid independent, common for all testedagents (novel pentadecapeptide BPC 157, cimetidine,ranitidine, omeprazole and atropine) could be clearlystressed.


Journal of Physiology-paris | 1999

The effect of pentadecapeptide BPC 157, H2-blockers, omeprazole and sucralfate on new vessels and new granulation tissue formation

Predrag Sikiric; Jadranka Separovic; Tomislav Anic; Gojko Buljat; Darko Mikus; Sven Seiwerth; Zeljko Grabarevic; Dinko Stančić-Rokotov; Biserka Pigac; Miroslav Hanzevacki; Anton Marovic; Rudolf Rucman; Marijan Petek; Ivan Zoricic; Tomislav Ziger; Gorana Aralica; Paško Konjevoda; Ingrid Prkačin; Miroslav Gjurasin; Pavle Miklic; Branka Artuković; Marina Tišljar; Mirna Bratulić; Stjepan Mise; Ivo Rotkvic

A clear protection of the gastrointestinal tract and an evident anti-inflammatory effect were shown for a novel stomach pentadecapeptide BPC 157 (i.p./i.g.) in comparison with several reference standards in various ulcer models along with a protection of endothelium and particular interaction with the NO-system. Thus, we evaluated whether this pentadecapeptide along with other gastroprotective agents could affect angiogenesis and the healing process in vivo using a procedure initially described by Szabo and co-workers. In each rat, two sterile sponges (1 x 1 x 0.25 cm; V = 0.25 mL) with the same quantities of BPC 157 (10 ng x mL(-1), 10 microg x mL(-1), 50 microg x kg(-1)) or reference agents (cimetidine: 10, 100, 500 mg x mL(-1); ranitidine: 2.5, 25, 250 mg x mL(-1); famotidine: 10, 50, 100 mg x mL(-1); omeprazole: 10, 50, 100 mg x mL(-1); sucralfate: 1, 5, 10 mg x mL(-1) were implanted subcutaneously in the lumbar region. The sponges were removed after 3 or 7 d, fixed in formalin, and processed for histologic and histochemical evaluation and morphometry assessment. Compared with the control values, the number of newly formed endothelial spaces inside newly formed granulation tissue was markedly increased in all animals treated with BPC 157, cimetidine, ranitidine, famotidine, sucralfate and omeprazole, a consistent finding noted after either 3 or 7 d. Compared with control values, markedly more granulation tissue was noted in the rats in the groups of animals treated with BPC 157 (50 microg) and in the rats treated with sucralfate in all dosages used, euthanized after 3 d. In all groups treated with H2-blockers however, similar values to those of controls were noted. Thus, it could be concluded that an evident angiogenic property was consistently noted for the novel pentadecapeptide BPC 157, H2-blockers (cimetidine, famotidine and ranitidine) and omeprazole, besides the well known angiogenic effect of sucralfate. Furthermore, unlike H2-blockers and omeprazole, BPC 157 stimulates the formation of granulation tissue, suggesting a particular activity, similar to that previously noted for sucralfate.


Digestive Diseases and Sciences | 1996

Salutary and prophylactic effect of pentadecapeptide BPC 157 on acute pancreatitis and concomitant gastroduodenal lesions in rats

Predrag Sikiric; Sven Seiwerth; Željko Grabarević; Rudolf Rucman; Marijan Petek; Vjekoslav Jagić; Branko Turkovic; Ivo Rotkvic; Stjepan Mise; Ivan Zoricic; Ljubica Jurina; Paško Konjevoda; Miro Hanževački; Danica Ljubanović; Jadranka Separovic; Miroslav Gjurasin; Mirna Bratulić; Branka Artuković; Nikola Jelovac; Gojko Buljat

The superior effectiveness of a new pentadecapeptide, BPC 157, on gastrointestinal and liver lesions, in conjunction with an antiinflammatory and analgetic activity was recently noted. In the present study, BPC 157 was tested as either a protective or healing agent in bile duct ligation-induced acute pancreatitis in rats. In addition, the positive influence of BPC 157 on concomitantly developed gastric and duodenal lesions was simultaneously investigated. BPC 157 (10 µg, 10 ng/kg body wt, intraperitoneally or intragastrically) was given prophylactically 1 hr before ligation, whereas the therapy was given once daily beginning with the 24 hr following ligation (last application 24 hr before killing). The effect was investigated at daily intervals until the end of the fifth day after ligation. In the pretreatment regimen, a strong pancreas protection was obtained. When applied in the condition of already established severe acute pancreatitis, an obvious salutary effect was consistently noted. Assessing the appearance of the necrosis, edema, neutrophils, and mononuclears, consistently less necrosis, edema, and neutrophils, but more mononuclears, were found in BPC-treated rats. Likewise, in studies of the serum amylase values, relative to control data, a markedly lower rise (BPC pretreatment regimen) as well as a worsening of the already raised values (BPC therapy regimen) was noted. Along with its beneficial effect on pancreatitis, a positive influence of BPC 157 on the gastric and duodenal lesion course in bile duct-ligated rats was noted in both the pre- and posttreatment regimen. Taken together, in further studies of acute pancreatitis therapy, BPC could be an interesting and useful agent with an additional positive impact on concomitant gastroduodenal pathology.

Collaboration


Dive into the Ivo Rotkvic's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge