Breaking News
May 3, 2019 - Vaping and Smoking May Signal Greater Motivation to Quit
May 3, 2019 - Dementia looks different in brains of Hispanics
May 3, 2019 - Short-Staffed Nursing Homes See Drop In Medicare Ratings
May 3, 2019 - Study of teens with eating disorders explores how substance users differ from non-substance users
May 3, 2019 - Scientists develop new video game that may help in the study of Alzheimer’s
May 3, 2019 - Arc Bio introduces Galileo Pathogen Solution product line at ASM Clinical Virology Symposium
May 3, 2019 - Cornell University study uncovers relationship between starch digestion gene and gut bacteria
May 3, 2019 - How to Safely Use Glucose Meters and Test Strips for Diabetes
May 3, 2019 - Anti-inflammatory drugs ineffective for prevention of Alzheimer’s disease
May 3, 2019 - Study tracks Pennsylvania’s oil and gas waste-disposal practices
May 3, 2019 - Creating a better radiation diagnostic test for astronauts
May 3, 2019 - Vegans are often deficient in these four nutrients
May 3, 2019 - PPDC announces seed grants to develop medical devices for children
May 3, 2019 - Study maps out the frequency and impact of water polo head injuries
May 3, 2019 - Research on Reddit identifies risks associated with unproven treatments for opioid addiction
May 3, 2019 - Good smells may help ease tobacco cravings
May 3, 2019 - Medical financial hardship found to be very common among people in the United States
May 3, 2019 - Researchers develop multimodal system for personalized post-stroke rehabilitation
May 3, 2019 - Study shows significant mortality benefit with CABG over percutaneous coronary intervention
May 3, 2019 - Will gene-editing of human embryos ever be justifiable?
May 3, 2019 - FDA Approves Dengvaxia (dengue vaccine) for the Prevention of Dengue Disease in Endemic Regions
May 3, 2019 - Why Tonsillitis Keeps Coming Back
May 3, 2019 - Fighting the opioid epidemic with data
May 3, 2019 - Maggot sausages may soon be a reality
May 3, 2019 - Deletion of ATDC gene prevents development of pancreatic cancer in mice
May 2, 2019 - Targeted Therapy Promising for Rare Hematologic Cancer
May 2, 2019 - Alzheimer’s disease is a ‘double-prion disorder,’ study shows
May 2, 2019 - Reservoir bugs: How one bacterial menace makes its home in the human stomach
May 2, 2019 - Clinical, Admin Staff From Cardiology Get Sneak Peek at Epic
May 2, 2019 - Depression increases hospital use and mortality in children
May 2, 2019 - Vicon and NOC support CURE International to create first gait lab in Ethiopia
May 2, 2019 - Researchers use 3D printer to make paper organs
May 2, 2019 - Viral infection in utero associated with behavioral abnormalities in offspring
May 2, 2019 - U.S. Teen Opioid Deaths Soaring
May 2, 2019 - Opioid distribution data should be public
May 2, 2019 - In the Spotlight: “I’m learning every single day”
May 2, 2019 - 2019 Schaefer Scholars Announced
May 2, 2019 - Podcast: KHN’s ‘What The Health?’ Bye-Bye, ACA, And Hello ‘Medicare-For-All’?
May 2, 2019 - Study describes new viral molecular evasion mechanism used by cytomegalovirus
May 2, 2019 - SLU study suggests a more equitable way for Medicare reimbursement
May 2, 2019 - Scientists discover first gene involved in lower urinary tract obstruction
May 2, 2019 - Researchers identify 34 genes associated with increased risk of ovarian cancer
May 2, 2019 - Many low-income infants receive formula in the first few days of life, finds study
May 2, 2019 - Global study finds high success rate for hip and knee replacements
May 2, 2019 - Taking depression seriously: What is it?
May 2, 2019 - With Head Injuries Mounting, Will Cities Put Their Feet Down On E-Scooters?
May 2, 2019 - Scientists develop small fluorophores for tracking metabolites in living cells
May 2, 2019 - Study casts new light into how mothers’ and babies’ genes influence birth weight
May 2, 2019 - Researchers uncover new brain mechanisms regulating body weight
May 2, 2019 - Organ-on-chip systems offered to Asia-Pacific regions by Sydney’s AXT
May 2, 2019 - Adoption of new rules drops readmission penalties against safety net hospitals
May 2, 2019 - Kids and teens who consume zero-calorie sweetened beverages do not save calories
May 2, 2019 - Improved procedure for cancer-related erectile dysfunction
May 2, 2019 - Hormone may improve social behavior in autism
May 2, 2019 - Alzheimer’s disease may be caused by infectious proteins called prions
May 2, 2019 - Even Doctors Can’t Navigate Our ‘Broken Health Care System’
May 2, 2019 - Study looks at the impact on criminal persistence of head injuries
May 2, 2019 - Honey ‘as high in sugars as table sugar’
May 2, 2019 - Innovations to U.S. food system could help consumers in choosing healthy foods
May 2, 2019 - FDA Approves Mavyret (glecaprevir and pibrentasvir) as First Treatment for All Genotypes of Hepatitis C in Pediatric Patients
May 2, 2019 - Women underreport prevalence and intensity of their own snoring
May 2, 2019 - Concussion summit focuses on science behind brain injury
May 2, 2019 - Booker’s Argument For Environmental Justice Stays Within The Lines
May 2, 2019 - Cornell research explains increased metastatic cancer risk in diabetics
May 2, 2019 - Mount Sinai study provides fresh insights into cellular pathways that cause cancer
May 2, 2019 - Researchers to study link between prenatal pesticide exposures and childhood ADHD
May 2, 2019 - CoGEN Congress 2019: Speakers’ overviews
May 2, 2019 - A new strategy for managing diabetic macular edema in people with good vision
May 2, 2019 - Sagent Pharmaceuticals Issues Voluntary Nationwide Recall of Ketorolac Tromethamine Injection, USP, 60mg/2mL (30mg per mL) Due to Lack of Sterility Assurance
May 2, 2019 - Screen time associated with behavioral problems in preschoolers
May 2, 2019 - Hormone reduces social impairment in kids with autism | News Center
May 2, 2019 - Researchers synthesize peroxidase-mimicking nanozyme with low cost and superior catalytic activity
May 2, 2019 - Study results of a potential drug to treat Type 2 diabetes in children announced
May 2, 2019 - Multigene test helps doctors to make effective treatment decisions for breast cancer patients
May 2, 2019 - UNC School of Medicine initiative providing unique care to dementia patients
May 2, 2019 - Nestlé Health Science and VHP join forces to launch innovative COPES program for cancer patients
May 2, 2019 - Study examines how our brain generates consciousness and loses it during anesthesia
May 2, 2019 - Transition Support Program May Aid Young Adults With Type 1 Diabetes
May 2, 2019 - Study shows how neutrophils exacerbate atherosclerosis by inducing smooth muscle-cell death
May 2, 2019 - Research reveals complexity of how we make decisions
New ointment for treating brown recluse spider bites is tested on humans

New ointment for treating brown recluse spider bites is tested on humans

The bite from a brown recluse spider (Loxosceles) can cause skin necrosis, renal failure, and even death. A new ointment is being tested in Brazil, however. Its effects have already been proven in tests conducted in cell cultures and animal models. Now the ointment will have its immunomodulatory action tested on humans in Phase III clinical trials, and it may be included in the treatment protocol for patients who develop lesions caused by the spider bite. The trial has started in October.

“There was extensive research into the action of the venom before development of the ointment. We were able to isolate and sequence the most important protein of the brown recluse spider venom for the first time 20 years ago. That allowed us to study the venom molecular action mechanisms and develop inhibitors, now patented, that can be used in studies of structure and function, and possibly as therapy,” said Denise Tambourgi researcher at the Butantan Institute, in a talk given at São Paulo Research Foundation – FAPESP Week New York/.

The meeting, held at the City University of New York (CUNY) November 26-28, 2018, involves Brazilian and U.S. researchers with the aim of strengthening research partnerships.

Clinical trials to verify the action of the ointment have just begun in Santa Catarina – a Brazilian state with a high incidence of brown recluse spider bites. “Clinical trials will be conducted on 240 people. Of this total, 120 will receive a placebo and the other 120 will be treated with the ointment. That will enable us to compare the results,” said Tambourgi who is also one of the principal investigators at the Center for Research on Toxins, Immune-Response and Cell Signaling – CeTICS, one of the FAPESP-funded Research, Innovation and Dissemination Centers – RIDCs.

Tetracycline, a substance used as an antibiotic, forms the basis of the ointment. “We utilized a concentration lower than a microbicide, but at a dosage able to modulate the activity of the protease that is involved in the process of tissue inflammation and destruction. Since tetracycline has already been tested in several clinical trials, it did not have to undergo tolerance phases (phases I and II). In fact, we are giving the substance a new use,” she said.

Cutaneous effect, systemic effect

In addition to causing cutaneous lesions – which could take months to heal – in some cases, the bite of a brown recluse spider also causes systemic effects such as hemolysis, platelet aggregation, renal inflammation and failure that can result in patient death.

There have been reports of accidents involving Loxosceles in South, Central, and North America. In recent years, however, cases of brown recluse spider bites have also occurred in Europe, with reports of cases in countries such as Spain, France, Portugal and Italy, a country that registered one case of fatal loxoscelism.

According to the Brazilian Ministry of Health’s National Disease Notification System – SINAN in 2016, there were 173,630 cases of accidents with venomous animals in Brazil, 7,441 of which were due to brown recluse spider bites.

Cutaneous loxoscelism occurs in nearly 80% of the cases. Less frequent but much more dangerous are the systemic effects that affect nearly 20% of patients bitten by the brown recluse spider.

Because the bite of the brown recluse spider is painless and reaction at the site does not appear immediately, victims only seek help when the skin lesion has already established itself. “Tissue necrosis is a result not just of the venom, but also of the cascade of reactions by the body itself, activated by the toxin’s main protein,” said Tambourgi.

For years, the Butantan Institute has produced limited quantities of serum for brown recluse spider bites. “They are small spiders, measuring 3 centimeters at most, from which we can extract little venom. We need hundreds of specimens to produce the serum,” Tambourgi said.

Secondary reactions

Studies to determine the key components of the brown recluse toxin have been conducted since 1994. The team of researchers from the Butantan Institute inserted a spider gene into the bacterium Escherichia coli, thus creating a biofabric of sphingomyelinase D (SMase D), the protein that is the core component of the toxin.

“During that entire process of research, we discovered that the venom of the brown recluse spider can cause secondary reactions that are triggered mainly by the protein. I often say that the toxin just begins the process and that the protein alters the cells. Later, deregulation of the body occurs, leading to the production of proteases – enzymes whose function is to break the peptide bonds of other proteins. These proteases are what the ointment has to inhibit,” she said.

Therefore, the ointment acts on the so-called secondary effect. “In experimental models both in vitro using human skin cells as well as in animal models, it was possible to reduce the size of the lesion by nearly 80%,” she said.

The study led by Tambourgi has determined the mechanism of action of the venom released by the brown recluse spider as well as the systemic and cutaneous form of the disease. “We were able to develop the ointment by building the mechanism that leads to the dermonecrotic lesion. However, because the poisoning is caused by what the protein induces in the body, we are attacking the secondary effects of the toxin. We have to await the results of the clinical trials, but I am confident because tests performed in cell cultures and animal models have been very promising,” she said.

Tagged with:

About author

Related Articles