Clínicas de beleza no Reino Unido estão oferecendo tratamentos controversos feitos a partir de extratos de células humanas, apesar de serem proibidos.  

  

Clínicas de beleza no Reino Unido estão oferecendo tratamentos controversos feitos a partir de extratos de células humanas, apesar de serem proibidos.  

Alternatively, if you prefer a slightly more formal or precise phrasing, you could also say:  

Clínicas de estética no Reino Unido estão disponibilizando tratamentos polêmicos produzidos com extratos de células humanas, mesmo sendo proibidos.  

Both versions convey the same meaning, with slight stylistic differences. The first is more direct, while the second uses synonyms like “estética”  for “beleza”  and “polêmicos”  for “controversos.” Choose based on the tone you prefer!
Britische Schönheitskliniken bieten umstrittene Behandlungen an, die aus menschlichen Zellextrakten hergestellt werden, obwohl diese verboten sind.  

(Alternative, slightly more natural phrasing:  
Trotz Verbots bieten Schönheitskliniken in Großbritannien umstrittene Behandlungen mit Extrakten aus menschlichen Zellen an.)  

Both versions convey the original meaning accurately, with the second option sounding slightly more fluid in German. The key terms are:  
– “controversial treatments” → *umstrittene Behandlungen*  
– “human cell extracts” → *Extrakte aus menschlichen Zellen* / *menschliche Zellextrakte*  
– “despite being prohibited” →