- Email: [email protected]
Herbal extract drug linked to liver cancer
ERIK JONSSON/EYEEM/GETTY
IN BRIEF Ice volcanoes make tiny worlds bright
Hunger-blocking injection causes rapid weight loss AN INJECTION that decreases appetite helps obese monkeys slim down fast and cuts their risk of diabetes. A protein called GDF15 naturally regulates body weight in humans and other animals. Several teams have tried developing GDF15 as an obesity treatment, but it breaks down too quickly in the bloodstream to work. Now a team led by Murielle Véniant at pharmaceutical company Amgen has found a way to make the protein last longer in the body, by adding an antibody fragment to it. The team found that this hybrid protein caused obese monkeys to eat about 40 per cent less. When given
weekly injections, the animals lost 10 per cent of their body weight over six weeks. Their glucose tolerance also improved, making them less likely to develop type 2 diabetes (Science Translational Medicine, doi.org/cfdn). In comparison, the five obesity medications currently approved by the US Food and Drug Administration for long-term weight management help patients lose an average of 7 to 12 per cent of their body weight over the course of a year. Bariatric surgery – the gold standard for weight loss – usually results in 20 to 30 per cent weight loss in obese patients in the first year, but is expensive and can have complications and side effects. Clinical trials will be needed to determine how well the new treatment works in people, and if it causes side effects like nausea, says Véniant.
Herbal extract drug linked to liver cancer A COMMONLY used Chinese herbal medicine causes genetic mutations linked to liver cancer. Extracts from the flowers, root or stem of around 100 species of Aristolochia have long been used to treat a wide range of conditions. But in 2013, researchers found that a compound in the plants, known as aristolochic acid, seems to cause a specific DNA mutation. “It attacks any part of the genome
with equal opportunity,” says Steven Rozen at the Duke-NUS Medical School in Singapore. When a member of Rozen’s team spotted the same type of mutation in liver cancer, the group wondered if plants that contain aristolochic acid might increase a person’s risk of developing the disease. The team looked for the mutation in 98 liver tumour
samples taken at two hospitals in Taiwan, where Aristolochia is used widely (Science Translational Medicine, doi.org/cfdm). “I was dumbstruck to find the evidence of exposure to aristolochic acid in 78 per cent of cases,” says Rozen. “This indicates strongly that aristolochic acid was one of the causes of these cancers.” Extracts from some Aristolochia species are banned in Taiwan, but others remain widely available, says Rozen.
HOW’S this for cool: the dwarf planets Eris and Makemake, which reside beyond Neptune, are probably home to ice volcanoes that continually recoat their surfaces with nitrogen frost. Judging by the amount of frozen methane the worlds have, we would expect a reddish aerosol gunk called tholin to colour their surfaces, making the worlds appear darker. Instead, they appear bright white, more like the regions of Pluto covered in nitrogen ice, according to work presented at an American Astronomical Society meeting on 17 October by Will Grundy at the Lowell Observatory and Orkan M. Umurhan at the SETI Institute. Grundy and Umurhan reason the dwarf planets must have ice volcanoes spewing nitrogen ice to cover the tholins. Since they are so far from the sun, Grundy says this activity may be driven by heat in radioactive rocks near their cores.
Bird gets angry at good singers TERRITORIAL songbirds in New Zealand react more aggressively towards males on their territory if their rivals’ songs are long and highly complex. Tui songbirds sing to defend their territories. Long and complex songs show endurance and skill, so good singers might be sterner rivals. Samuel Hill at Massey University in Auckland, New Zealand, and his colleagues used a speaker to play simple or complex tui songs near male tui, as well as a control song from another species of bird. After complex songs, male tui approached the speaker faster, got closer and sang more complex songs (Ibis International Journal of Avian Science, doi.org/cfdt). 28 October 2017 | NewScientist | 17
IN BRIEF Ice volcanoes make tiny worlds bright
Hunger-blocking injection causes rapid weight loss AN INJECTION that decreases appetite helps obese monkeys slim down fast and cuts their risk of diabetes. A protein called GDF15 naturally regulates body weight in humans and other animals. Several teams have tried developing GDF15 as an obesity treatment, but it breaks down too quickly in the bloodstream to work. Now a team led by Murielle Véniant at pharmaceutical company Amgen has found a way to make the protein last longer in the body, by adding an antibody fragment to it. The team found that this hybrid protein caused obese monkeys to eat about 40 per cent less. When given
weekly injections, the animals lost 10 per cent of their body weight over six weeks. Their glucose tolerance also improved, making them less likely to develop type 2 diabetes (Science Translational Medicine, doi.org/cfdn). In comparison, the five obesity medications currently approved by the US Food and Drug Administration for long-term weight management help patients lose an average of 7 to 12 per cent of their body weight over the course of a year. Bariatric surgery – the gold standard for weight loss – usually results in 20 to 30 per cent weight loss in obese patients in the first year, but is expensive and can have complications and side effects. Clinical trials will be needed to determine how well the new treatment works in people, and if it causes side effects like nausea, says Véniant.
Herbal extract drug linked to liver cancer A COMMONLY used Chinese herbal medicine causes genetic mutations linked to liver cancer. Extracts from the flowers, root or stem of around 100 species of Aristolochia have long been used to treat a wide range of conditions. But in 2013, researchers found that a compound in the plants, known as aristolochic acid, seems to cause a specific DNA mutation. “It attacks any part of the genome
with equal opportunity,” says Steven Rozen at the Duke-NUS Medical School in Singapore. When a member of Rozen’s team spotted the same type of mutation in liver cancer, the group wondered if plants that contain aristolochic acid might increase a person’s risk of developing the disease. The team looked for the mutation in 98 liver tumour
samples taken at two hospitals in Taiwan, where Aristolochia is used widely (Science Translational Medicine, doi.org/cfdm). “I was dumbstruck to find the evidence of exposure to aristolochic acid in 78 per cent of cases,” says Rozen. “This indicates strongly that aristolochic acid was one of the causes of these cancers.” Extracts from some Aristolochia species are banned in Taiwan, but others remain widely available, says Rozen.
HOW’S this for cool: the dwarf planets Eris and Makemake, which reside beyond Neptune, are probably home to ice volcanoes that continually recoat their surfaces with nitrogen frost. Judging by the amount of frozen methane the worlds have, we would expect a reddish aerosol gunk called tholin to colour their surfaces, making the worlds appear darker. Instead, they appear bright white, more like the regions of Pluto covered in nitrogen ice, according to work presented at an American Astronomical Society meeting on 17 October by Will Grundy at the Lowell Observatory and Orkan M. Umurhan at the SETI Institute. Grundy and Umurhan reason the dwarf planets must have ice volcanoes spewing nitrogen ice to cover the tholins. Since they are so far from the sun, Grundy says this activity may be driven by heat in radioactive rocks near their cores.
Bird gets angry at good singers TERRITORIAL songbirds in New Zealand react more aggressively towards males on their territory if their rivals’ songs are long and highly complex. Tui songbirds sing to defend their territories. Long and complex songs show endurance and skill, so good singers might be sterner rivals. Samuel Hill at Massey University in Auckland, New Zealand, and his colleagues used a speaker to play simple or complex tui songs near male tui, as well as a control song from another species of bird. After complex songs, male tui approached the speaker faster, got closer and sang more complex songs (Ibis International Journal of Avian Science, doi.org/cfdt). 28 October 2017 | NewScientist | 17